Crispy Sweet Potato Fries (Oven Baked)

Jump to Recipe Print Recipe

These oven-baked sweet potato fries are crispy, easy to make and completely delicious! Perfectly seasoned with your favourite spices, they bake in the oven in less than 25 minutes and are perfect as a healthy appetiser or side dish for any occasion.

a plate of sweet potato fries on a table with dipping sauces.

Why you’ll love this recipe

Healthy – no deep fryer required! With just 2-3 tablespoons of oil, this recipe is healthy and full of fibre.
Versatile – serve them with your favourite dipping sauce as an appetiser or to accompany a main meal like these crispy chicken burgers, healthy chilli con carne, chicken pies or cheeseburgers.
Quick and easy – this recipe is made with just a few simple steps. Just chop the sweet potatoes, soak (optional), season and bake.
Customisable – these fries have the best texture. Crispy on the outside and soft and tender inside. And you can customise the flavour by adding your favourite seasonings. See the recipe variations below.
They make a great vegetarian side dish.

Ingredients you will need

** This post contains tips and instructions to achieve the best possible results. This photo is a great guide for when you are in the supermarket, but for full ingredient quantities and methods, please scroll down to the detailed recipe card below!

all ingredients for sweet potato fries, laid out on a table.

Sweet potatoes – you will need 3-4 medium-sized sweet potatoes, (approximately 1.3 kg). Choose sweet potatoes that are firm, with bright peel and no soft spots. I like to peel them first, but you can leave the skin on if you prefer.
Vegetable oil – olive oil or avocado oil can be used if preferred, but a high smoke point oil like vegetable, canola or peanut will make crispier fries.
Cornflour – also called corn starch, cornflour is the key ingredient for crispy fries. Cornflour is used to coat the fries and helps to absorb the moisture in the sweet potatoes, leaving them crunchy and crisp. If you require gluten-free fries, make sure the cornflour you use doesn’t contain wheat.
Seasonings – I use paprika (make sure it’s sweet Hungarian paprika and not hot or smoked), but black pepper, garlic powder, Cajun seasoning, rosemary and cayenne are great additions. Feel free to use this recipe as a base and add any of your favourite seasonings.
Salt – to sprinkle at the end.

Step by step instructions

Full ingredient notes and quantities can be found in the detailed recipe card below. But here is a brief overview of what you can expect;

Cut the fries – peel and slice the sweet potatoes into evenly-sized matchsticks, about 6-7mm (¼ inch) wide. Try to keep the size of the fries consistent, for even baking.
Soak in cold water – for extra crispy fries, soak them in cold water for at least 30 minutes (or leave them to soak in the fridge overnight). This step is optional if you are short on time, but will remove some of the starch from the sweet potatoes which yields crispier fries. Rinse, drain and thoroughly dry.
Toss in oil – add the fries to a clean bowl and coat with the oil.
Coat – add the cornflour and paprika (or your choice of spices) and mix until completely coated.
Bake – transfer the fries to oven trays lined with baking paper. The fries should be arranged in a single layer, without touching or they will steam and become soggy.
Turn halfway – turn the fries after 15 minutes and continue to bake for a further 8-10 minutes, or until golden on the outside and tender in the middle.

peeled whole sweet potatoes on a wooden board.

sliced sweet potato fries on a wooden board.

sweet potato fries soaking in a bowl of water.

sweet potato fries in a bowl, coated in cornflour and spices.

sweet potato fries arranged on a baking tray.

Expert tips

Cut the fries evenly – cut the sweet potatoes into matchsticks, about 6-7mm wide and take the time to cut them to mostly the same size. This will help the fries to cook evenly and get nice and crispy.
Soak them in cold water – once the fries have been cut, transfer them to a bowl and cover with cold water. Soaking them for at least 30 minutes (or in the fridge overnight) will remove the excess starch in the potatoes, helping them to crisp up nicely in the oven. You can prep ahead and soak the cut sweet potato for up to 24 hours before drying and baking.
Dry them thoroughly – after soaking, make sure you dry the fries with paper towel or a clean towel until no moisture remains before coating them in the oil and cornflour.
Don’t skip the cornflour. It’s essential for perfectly crispy fries.
Seasoning – feel free to use this recipe as a base and add any of your favourite seasonings for fries. I use paprika (make sure it’s sweet Hungarian paprika and not hot or smoked), but black pepper, garlic powder, Cajun seasoning, rosemary and cayenne are great additions.
Use baking paper to stop the fries from sticking to the oven tray.
Don’t crowd the fries! Arrange the fries on the baking trays in a single layer. As the sweet potato cooks, it will release steam. If the fries are crowded too closely together, they will steam and your fries will become soggy. Aim for a single layer and use more than one tray, if needed.
Before baking, make sure your oven is completely pre-heated and the rack is in the middle of the oven. Fries will burn if too close to the bottom of the oven. For best baking results, use an oven thermometer.
Make sure you flip all the fries. After 15 minutes, use tongs to gently flip the fries over.
Baking times can vary based on your oven and the size of your fry cut. Flip them at 15 minutes and then keep an eye on them so they don’t burn. The fries should be crispy and golden on the outside and soft and tender in the middle.
Storage; these chips are best eaten fresh, straight from the oven. But leftovers can be stored in an airtight container in the fridge for 2-3 days. Reheat them in the oven or air fryer until steaming hot in the middle.

FAQs

Why are my sweet potatoes not crispy?

If your fries are soggy and did not crisp, it is likely that they have been cut too thick, are unevenly sized, the tray has been overcrowded or the oven wasn’t hot enough. Make sure that the fries are on the thinner side and mostly uniform in size. Ensure they are completely patted dry before adding the cornflour and spice mixture and spread them in a single layer on the baking tray.

Can I make them in an air fryer?

These fries can be cooked in an air fryer. Preheat the air fryer to 200 C/392 F. Place the seasoned sweet potato fries into the air fryer basket in a single layer (you may need to cook in batches to achieve this). Air fry for 10-15 minutes, or until crispy and golden and tender in the middle. Flip the fries 1-2 times while cooking.

Do I have to soak the fries?

This recipe will still result in deliciously tasty fries if you don’t have time to soak them. But you will achieve much crispier results if you soak them first. Soaking your fries in cold water will draw out some of the excess starch in the sweet potato, making them crispy on the outside and tender in the middle. Once the fries have been soaked, you will see a pool of white starch in the bottom of the bowl. Drain and rinse them under cold water and dry them thoroughly, so that there is no moisture remaining.

sweet potato fries on a tray with bowls of dipping sauce.

Tried this recipe? Please leave a star ⭐⭐⭐⭐⭐ rating or leave a review below and let you know how you went!

Hungry for more? Subscribe to my newsletter and follow along on Facebook, Instagram and Pinterest for the latest recipes and news.