How to Prepare French Fries in a Convection Oven

A convection oven is the perfect tool for turning out crispy oven-baked fries every time. Because a fan circulates hot air throughout the oven, your fries will cook up faster and more evenly ⁠— and lose fewer nutrients thanks to their reduced cooking time.

If you've purchased store-bought frozen fries, you can cook them by following the instructions on the back of the package. However, the fact that you're using a convection oven changes those instructions slightly.

One change is in the cook temperature: Most experts recommend reducing your cooking temperature by about 25 degrees Fahrenheit to convert a conventional oven for use in a convection oven.

As the University of Kentucky notes, convection ovens also cook your food up to 25 percent faster. This conversion isn't an exact science, so if the package recommends baking your fries at 400 degrees Fahrenheit for 20 minutes, set the convection oven to 375 F and check the fries for doneness after no more than 15 minutes.

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If you're concerned about the additives or high fat or sodium content in store-bought fries, take control of your health — and your taste buds — by making your own convection oven french fries from scratch. It's easier than you might think.

Start by choosing firm, unblemished potatoes. For an extra nutrient boost, use sweet potatoes, which according to the USDA contain notable amounts of important nutrients including calcium, phosphorus, potassium and several B vitamins. Harvard's The Nutrition Source also notes that sweet potatoes with orange flesh are rich in beta-carotene, a precursor to vitamin A.

If you're particularly adventurous, try different potato varieties from a local farmer's market — although you may have to experiment to find the right cooking time for each. Generally, the starchier varieties work best for creating crisp oven-made french fries — as long as they're correctly prepped.

Scrub the potatoes and cut them into long, thin strips. Peeling is optional; leaving the potato skin on helps preserve more of the nutrients.

Once you've sliced the potatoes, submerge them in a bowl of cold water for 15 to 30 minutes. Remove the potatoes; rinse them thoroughly in cold water, and then spread them out on a towel or paper towels and thoroughly pat them dry. This soak-rinse-dry process helps ensure crispy fries as an end product.

If your convection oven has an "air fry" or "super convection" setting, use it — this will give you the crispiest oven fries in the shortest time.

Otherwise, preheat the convection oven to 375 to 425 degrees as you season the potato slices. Toss your raw potato slices with a couple of tablespoons of olive oil until they're thoroughly coated. Any additional seasoning is optional. Consider adding sea salt, ground black pepper, rosemary or even a very light touch of cayenne pepper. Or experiment with using oils that are already flavored by herbs and spices.

Spread the potato slices evenly in a single layer on a baking sheet, or, for even better results, spread them on a baking rack placed on a baking sheet. Try to keep the potato slices from touching.

Bake the potato slices until golden brown — usually 30 to 45 minutes. Cook time will vary depending on the thickness of your potato slices, oven temperature and simply between ovens, so keep an eye on the first batch until you get a feel for how long the process takes in your oven.

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