How to make frozen roast potatoes crispy

Here's a quick trick to take frozen roast potatoes to the next level by infusing them with rosemary and garlic and seasoning with a good helping of cracked black pepper.

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How to make frozen roast potatoes crispy

As much as I love cooking from scratch, on occasions where there's a big roast to cook with loads of trimmings, I'm a big fan of ready-to-roast potatoes.

Over the holidays especially, there's so much to do that being able to tip potatoes straight into a roasting tin and have them ready in half an hour is a huge help.

And to please even fussy eaters, I like to posh them up a bit.

Delicious, super quick and rather festive.

Ingredients

  • 1.4 kg (3 lb) frozen roast potatoes
  • 8 sprigs fresh rosemary
  • 1 jumbo (1 bulb) garlic bulb
  • 1 pinch salt and pepper to taste

Equipment

Instructions

Preheat the oven to 230C (210C fan assisted). Tip the potatoes into a large roasting tray and spread evenly.

How to make frozen roast potatoes crispy

Rub the rosemary leaves gently between your hands a few times to help release the flavour then tuck in amongst the potatoes. Break open the garlic bulb and put the cloves, lightly crushed but still with skins, in amongst the potatoes. Season with plenty of freshly milled black pepper, and a little salt, if desired.

How to make frozen roast potatoes crispy

Bake for 30-40 minutes (according to pack instructions), then serve.

How to make frozen roast potatoes crispy

If you love garlic like I do, you can also squeeze the softened, roasted cloves out of their skins and eat them whole. Delicious!

How to make frozen roast potatoes crispy

Pointers, tricks and troubleshooting tips for the perfect pimped up packet roast potatoes, infused with rosemary and garlic

Are pimped up packet roast potatoes, infused with rosemary and garlic easy to make?

This is such a simple recipe and adds so much flavour to these ready to cook roasties, saving you precious time when your juggling all the other elements of a delicious roast dinner.

It’s the perfect recipe to take some of the pressure off and gives these potatoes a beautiful homemade touch that really lifts them. 

Will I need any special equipment for this recipe?

You won’t need any special equipment for this recipe, not even a potato peeler!

You should be able to find everything you need in the average kitchen, a large baking tray, and a chopping board and knife to prepare the garlic. 

Where can I buy ready-to-cook roast potatoes?

You should be able to find ready-to-cook roast potatoes in the freezer section of the supermarket. 

How can I tell if garlic has gone off?

As with a lot of things, it's a case of using your senses and with a few tips you should be able to easily tell if you’re garlic is still ok to use.

Fresh garlic will feel firm and be pale almost white in colour. If your garlic feels soft or has brown spots it's well past its best and probably not save to use.

If your garlic has started sprouting green shoots it's still ok to use! These shoots will bring a more bitter taste so in recipes where you’re chopping or mincing the garlic it's a good idea to remove them, they pop out quite easily once the garlic is cut in half.

You can cut any green tops off for this recipe but we’re leaving the skins on so you won’t be able to remove the whole shoot. This shouldn’t be a problem as we’re using the garlic to infuse flavour rather than to necessarily eat whole. 

Garlic can keep for up to 6 months, its best stored in a cool dark stop in a paper bag, or just loose, don’t keep it in a sealed container or in the fridge unless it’s been peeled. 

Are pimped up packet roast potatoes, infused with rosemary and garlic suitable for vegetarians or vegans?

This will all depend on the ready-made potatoes you’re using. A lot of traditional roast potato recipes use duck fat or beef dripping, which is recreated in many ready-made roasties so make sure to find a packet that uses vegetable oil if you are making these for a vegetarian or vegan. 

Are pimped up packet roast potatoes, infused with rosemary and garlic gluten-free?

If you’re making these for someone who needs to avoid gluten in their diet its important to check the ingredients on the ready-made roast potatoes, they don’t usually contain wheat flour but it's always best to check

Are pimped up packet roast potatoes, infused with rosemary and garlic safe to eat while pregnant?

There is nothing in this recipe that should pose a risk to a pregnant woman as long as good food hygiene is practiced and the roasties are properly cooked. 

A Mummy Too does not give medical advice, if you have any questions or concerns please speak to a health professional. 

Are pimped up packet roast potatoes, infused with rosemary and garlic suitable for babies and toddlers?

Yes, if the baby is over six months old and happily eating solid food then these pimped up roast potatoes are ok for them. If these potatoes are being served to a baby or young children, don’t add any salt seasoning before cooking, the adults can add salt at the table if they wish. 

It’s important to supervise little ones while they are eating, make sure they are sitting up straight to reduce the risk of choking. Cut up the potatoes into small manageable pieces for them and allow the potatoes to cool before serving. 

What goes well with Are pimped up packet roast potatoes, infused with rosemary and garlic?

These potatoes are the perfect addition to any roast dinner, and especially good for a Thanks Giving or Christmas feast as they take some of the pressure off and time spent peeling potatoes! 

Can I make this recipe without garlic?

If you don’t like garlic or don't have any fresh garlic you can leave it out no problem. These roasties are just as yummy with just rosemary

I haven’t got rosemary, can I use sage?

It’s best to use a more hardy herb like thyme if you don’t have any rosemary, soft herbs like sage will likely burn in the oven.

How should I store pimped up packet roast potatoes, infused with rosemary and garlic?

As these potatoes are ready-made, it's best to check the packet for more detailed instructions. Once cooked, it should be ok to cool and keep any leftovers in the fridge for a couple of days. Make sure to cool and pop them into a sealed container and into the fridge as quickly as you can.

How long do pimped up packet roast potatoes, infused with rosemary and garlic keep?

Please check packet instructions for further information, leftovers should be ok in the fridge for a couple of days. 

Can I leave pimped up packet roast potatoes, infused with rosemary and garlic out on the counter?

No, other than for serving, any leftovers need to be put in the fridge to reduce the risk of bacterial spread. 

Can I make pimped up packet roast potatoes, infused with rosemary and garlic ahead?

As we’re using ready-made roasties most of the work is done for us, if you want to get ahead and save 5 minutes you can prepare the rosemary and garlic in the morning and keep it in the fridge in a sealed container ready to combine with the potatoes in time for lunch or dinner.

The potatoes should be cooked from frozen, and don’t need to be defrosted before cooking. 

Can I keep pimped up packet roast potatoes, infused with rosemary and garlic in the refrigerator?

Once cooled, yes do keep any leftovers in the fridge. 

Can I freeze pimped up packet roast potatoes, infused with rosemary and garlic?

Probably not, most ready-made potatoes advise they are not suitable for refreezing so double-check the packet. 

What is the best way to reheat pimped up packet roast potatoes, infused with rosemary and garlic?

You can either reheat these in the microwave or oven, only reheat leftover potatoes once after the initial cooking, after this they will need to be discarded. 

Keep in mind if you reheat these in the microwave they won’t crisp up, pop them onto a microwave plate and loosely cover, heat on full for 2-4 minutes until the potatoes are steaming hot. 

To reheat in the oven, preheat the oven to 200C(180C fan) put the potatoes onto a baking tray, and heat in the oven for 15-20 minutes, check they are piping hot before serving. 

Can I make pimped up packet roast potatoes, infused with rosemary and garlic in a different quantity?

Yes, it's so simple to make more or less of these amazing jazzed-up roast potatoes.

On the recipe card below you’ll see the servings is set to 6, which uses one large bag of ready-made potatoes.

Click on the number of servings and a slider will pop up that you can move up or down to get the number of servings you want to make. The ingredients will update automatically so you’re ready to go. 

Can I make pimped up packet roast potatoes, infused with rosemary and garlic in individual portions?

This is the kind of recipe that is easier to make all in one go to get an even distribution of the aromatic rosemary and garlic.

You can of course serve these into individual portions in small side dishes or straight out onto people's plates if you wish. 

Can I make pimped up packet roast potatoes, infused with rosemary and garlic in the air fryer?

As we’re adding aromatics it's probably easier to use a regular oven, because they may fall through the basket depending on your model. 

That said you may be able to use an air fryer, check the packet instructions and the user guide for your air fryer to see if it would be suitable. 

How can I make sure pimped up packet roast potatoes, infused with rosemary and garlic are perfectly cooked?

The oven is probably already on for your roast, but make sure it's preheated and come up to temperature to make sure these potatoes are cooked thoroughly and become lovely and crisp.

When I’m doing a big roast dinner I find it helpful to note down all the different cooking times, working backward from when I want it to be ready.

This helps me keep track of when everything needs to come in and out of the oven. Remember you don’t want to keep opening the oven as it lets out all the heat so try and synchronize things coming in and out at the same time as much as you can. Have some heat mats ready on the worktop so you're not juggling hot trays!

Why did my pimped up packet roast potatoes, infused with rosemary and garlic turn out dry and burnt?

The garlic may catch a little, and that's not a problem, this is why we left the skins on, you can pop the garlic out of the skin and it will be beautifully soft and delicious inside. 

Make sure to set a timer so you get the potatoes out of the oven when they are ready. You can wrap them into a tin foil parcel to protect them from burning in the oven if they are ready early. 

Why did my pimped up packet roast potatoes, infused with rosemary and garlic taste bland?

This recipe is a great way to add flavour to ready-made potatoes, you can adjust the seasoning to your tastes, try adding some more salt and pepper if you like. 

Want to try this recipe later? Hit the 'PRINT' button on the recipe card below.

Pimped up Packet Roast Potatoes, Infused with Rosemary and Garlic

A quick trick to take frozen roast potatoes to the next level by infusing them with rosemary and garlic and a good helping of cracked black pepper.

Prep Time5 mins

Cook Time30 mins

Total Time35 mins

Course: Dinner

Cuisine: British

Diet: Vegetarian

Servings: 6 servings

  • 1.4 kg (3 lb) frozen roast potatoes
  • 8 sprigs fresh rosemary
  • 1 jumbo (1 bulb) garlic bulb
  • 1 pinch salt and pepper to taste

  • Preheat the oven to 230C (210C fan assisted / 450F). Tip the potatoes into a large roasting tray and spread evenly.

  • Rub the rosemary leaves gently between your hands a few times to help release the flavour then tuck in amongst the potatoes. Break open the garlic bulb and put the cloves, lightly crushed but still with skins, in amongst the potatoes. Season plenty of freshly milled black pepper, and a little salt, if desired.

  • Bake for 30-40 minutes (according to pack instructions), then serve.

Calories: 607kcal | Carbohydrates: 70g | Protein: 7g | Fat: 35g | Saturated Fat: 11g | Sodium: 1150mg | Potassium: 1003mg | Fiber: 11g | Sugar: 1g | Vitamin C: 15mg | Calcium: 21mg | Iron: 3mg

* Note: nutritional information is estimated, based on publicly available data. Nutrient values may vary from those published. Information on this website should not be taken as medical advice. Cuisines identify the primary region of inspiration for a dish.

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Pin these roast potatoes

How to make frozen roast potatoes crispy
How to make frozen roast potatoes crispy
How to make frozen roast potatoes crispy
How to make frozen roast potatoes crispy
How to make frozen roast potatoes crispy
How to make frozen roast potatoes crispy

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How to make frozen roast potatoes crispy

How do you crisp up pre cooked roast potatoes?

Set your temperature around 150-200 degrees C 350-400 degrees F, depending on the air fryer you have. Reheat your potatoes for around 3-4 minutes, and afterwards, check on your potatoes. Cook the potatoes until they're as crisp as you need them to be, and then serve!

How do you cook frozen roast potatoes?

There's no need to thaw your roast potatoes before cooking them. I recommend using the oven to reheat frozen roast potatoes. Preheat the oven to 400ºF (200ºC) with a greased baking tray inside. Then arrange the potatoes on the baking sheet and heat them for 20-23 minutes, flipping periodically.

Why won't my roast potatoes crisp up?

To make crispy roast potatoes, the temperature of the oven needs to be hot 220°C or 425°F - but if the oven is too hot the potatoes will burn before they crisp up. What is this? If the oven temperature is too cold your potatoes will not be crispy.

Does freezing potatoes make them crispy?

Freezing potatoes that you plan to roast not only saves time but can actually make for extra crunchy spuds. Peel potatoes, if desired, then cut into wedges, cubes or chunks and blanch in boiling water until they are tender but still have some bite.