Sweet Potato Fries

Ingredients

• 1.36 kg (3 lb)sweet potatoes, cut into 6 mm (¼-inch) strips
• 60 ml (¼ cup)olive oil
• 8 g (1 tbsp)cornflour
• 2 tspdark chilli powder, more or less to taste
• 8 g (2 tsp)granulated sugar
• 5 g (1 tsp)salt
• ½ tspgranulated garlic or garlic powder
• ½ tsponion powder
• ½ tspground cumin
• ¼ tspground cinnamon
• As neededcooking spray

Instructions

1. 1

   Prepare the trays

   Heat the oven to 220°C (425°F). Line two large rimmed baking trays with foil and spray them generously with cooking spray; set aside.

2. 2

   Soak the potatoes

   Scrub the sweet potatoes, peeling them if you prefer, then cut into strips about 6 mm (¼ inch) thick. Put them in a large bowl of cold water and soak for at least 30 minutes and up to 4 hours. Drain thoroughly and pat dry.

3. 3

   Coat with oil

   Put the sweet potato strips in a large food-storage bag and drizzle over the olive oil. Seal the bag and toss until the strips are coated.

4. 4

   Add the seasoning

   Whisk the cornflour, chilli powder, sugar, salt, garlic powder, onion powder, cumin and cinnamon together in a small bowl. Add the mixture to the potatoes, seal the bag and shake until evenly coated.

5. 5

   Bake until tender

   Spread the sweet potatoes in a single layer across the prepared trays. Bake for 30–40 minutes, turning them once halfway through, until golden brown and tender.

6. 6

   Serve straight away

   Serve immediately with comeback sauce or your favourite aioli for dipping.

What are sweet potato fries?

Sweet potato fries are a familiar American-style side: strips of sweet potato roasted or fried until browned at the edges and soft inside. This version uses the oven, so you can cook a large batch without deep-frying.

Cornflour and a short soak are the key choices here. The coating adds a light outer layer, while the seasoning balances the potatoes’ sweetness with chilli, cumin, garlic and a hint of cinnamon.

Nutrition and macros by portion

The nutrition label shows one serving as written: 217 calories, 3g protein, 37g carbs, 7g fat.

The sweet potatoes provide most of the carbohydrates, while the olive oil supplies most of the fat. There is a modest amount of protein, mainly from the sweet potatoes; pair a serving with a protein-rich main and vegetables to balance the plate.

Why soak the strips?

Cold-water soak: the recipe gives a range of at least 30 minutes and up to 4 hours. This step is followed by thorough draining and drying, so the coating can cling rather than being diluted by water.

Dry well: pat the strips with a clean tea towel or kitchen paper after draining. Damp potatoes can release steam on the trays instead of roasting cleanly.

The coating and seasoning

Cornflour: toss it with the spices before adding it to the bag, which helps distribute the mixture around the strips. Shake until the coating looks even.

Spice balance: dark chilli powder brings warmth, while sugar, cumin and cinnamon give the fries a sweet-and-savoury flavour. Adjust the chilli to taste, as the recipe allows.

Make room on the trays

Single layer: spread the strips out across both trays rather than piling them up. If they overlap, they are more likely to soften from trapped steam than brown.

Even sizing: cut the strips to roughly the same 6 mm thickness. This helps them finish cooking at a similar time.

Check the texture

Turning point: turn the fries once halfway through the 30–40-minute bake. This gives the other sides contact with the hot tray.

Doneness: look for golden-brown edges and a tender centre. Begin checking towards the shorter end of the baking time, since oven and tray differences can affect how quickly they cook.

Serve while hot

These fries are best served straight from the oven, when their edges are at their freshest. Offer comeback sauce or aioli for dipping, as suggested in the recipe.

They also pair well with burgers, sandwiches or grilled steak. Add a crisp green salad or another vegetable side for a more rounded plate.

Recipe notes & tips

• Cut the strips to a similar thickness so they cook evenly.
• Give the potatoes a full soak of at least 30 minutes, then dry them thoroughly.
• Shake the bag well after adding the seasoning to coat the strips evenly.
• Use both trays and leave space around the fries to encourage browning.
• Turn the fries once halfway through baking.
• Serve them immediately for the best freshly roasted texture.

Variations

• Milder seasoning: use less chilli powder for a gentler heat.
• More chilli: increase the chilli powder to taste for a warmer finish.
• Extra garlic: use the granulated garlic option and adjust it to your liking.
• Herby finish: scatter chopped fresh herbs over the fries just before serving.
• Different dip: serve with another favourite aioli or dipping sauce.

Common mistakes to avoid

• Wet strips: excess water can hinder browning; drain well and pat the potatoes dry.
• Crowded trays: overlapping strips can steam; spread them in a single layer over two trays.
• Uneven cutting: thicker pieces take longer to soften; aim for strips about 6 mm wide.
• Patchy seasoning: adding the mixture all at once in a bowl can leave bare spots; shake the sealed bag until coated.
• Skipping the turn: one side may brown more than the other; turn the fries halfway through.
• Overbaking: the strips can become too dark or dry; check for golden edges and tenderness within the 30–40-minute window.

How to store

Cool leftovers and refrigerate them in an airtight container for up to 3 days. Reheat in a hot oven until warmed through; they will be softer than when freshly baked.

Frequently asked questions