Homemade sweet potato fries in the Ninja Crispi

To get real Ninja Crispi sweet potato fries that do not go soft after cooking, soaking them in cold water is essential. This bath removes surface starch, and thorough drying afterwards prevents steam from forming in the container. The 3.8 L glass container takes 700 g in one go, enough for 3 to 4 people.

On my FN101 Crispi, this method avoids the mushy effect too often observed with this vegetable. Once properly dried before being oiled, the sticks gain a firm exterior and a well-cooked core.

Homemade sweet potato fries in the Ninja Crispi

Recipe by Marion LundCourse: Side dishCuisine: AmericanDifficulty: Easy

Servings

3-4

portions

Prep

40

minutes

Cook

22

minutes

Total time

1

hour 

2

minutes

Evenly sized, soaked, dried, and air-fried sweet potato fries for a homemade side dish without frying.

Ingredients

• 700 g sweet potatoes (peeled)

• 1 tbsp neutral oil or olive oil

• 1/2 tsp fine salt

• 1/2 tsp mild paprika (optional)

Instructions

• Cut the sweet potatoes into even sticks about 1.5 cm thick. Soak them in a large bowl of cold water for 30 minutes to remove excess starch. The water will become slightly cloudy.
• Drain the sticks and dry them very carefully with a clean tea towel or paper towel. The surface of the fries must be completely dry to the touch before proceeding.
• In a dry bowl, toss the fries with the oil, salt, and paprika. Ensure each stick is well coated for an even distribution of the fat.
• Place the crisper plate at the bottom of the 3.8 L container. Arrange the sweet potato fries trying not to overcrowd them, to allow air to circulate.
• Place the adapter and the PowerPod on the container. Select the Air Fry mode and set the time for 18 to 22 minutes. Press START.
• After 8 minutes, and again at 15 minutes of cooking, lift the PowerPod to pause. Shake the container or stir with silicone-tipped tongs. Replace the PowerPod and press START. The tips will start to brown and the fries will shrink slightly towards the end.

Frozen sweet potato fries

If using frozen sweet potato fries on the Crispi, cook them directly in Air Fry mode: 500 g for 14 to 17 minutes in the 3.8 L container, 230 g for 12 to 14 minutes in the 1.4 L, tossing 2 to 3 times. Do not add oil or defrost beforehand.

The right container and setting for your device

Sweet potato needs space to evaporate its water without steaming. The Air Fry mode is the range’s direct setting for this type of preparation. The choice of container dictates the possible quantity and the number of shakes needed to brown each side evenly.

The basic Crispi is controlled by time, with no temperature setting. The times below are for fresh sweet potato in 1.5 cm pieces: I use them for sticks 1.5 cm thick.

• Crispi with 3.8 L container: 700 g of fries with 1 tbsp of oil, for 18 to 22 minutes, tossing 2 to 3 times.
• Crispi with 1.4 L container: limit the amount to 200 g maximum (with 1 tsp of oil) for 15 to 20 minutes, tossing 2 to 3 times.
• Crispi Pro and Pro 5 modes: Air Fry at 180 °C. Allow 15 to 20 minutes for 450 g (1 tbsp of oil) in the 2.3 L container, tossing twice, and 25 to 30 minutes for 900 g in the 5.7 L container, tossing 2 to 3 times.
• DualZone: Air Fry at 200 °C, 15 to 20 minutes for 750 g (1 tbsp of oil) per 3.8 L container, tossing halfway through cooking.

Getting texture and avoiding soft fries

Soft sweet potato fries are caused by excess moisture. Soaking removes surface starch, but rigorous drying with a tea towel determines the final result. If the sticks are still wet when you oil them, that water turns to steam in the container, and the sweet potato steams instead of browning.

Overloading the small container has the same effect. Hot air stops at the top layer: the bottom fries cook in their own juices while those on top brown too fast. Stick to 200 g in the 1.4 L container.

Monitor the cooking through the glass during the final shake. The visual cue for end of cooking is clear: the tips of the fries start to caramelise and the whole stick loses a little volume. If the underside remains pale, put the PowerPod back, add a few minutes of Air Fry and press START.

Organisation and reheating without drying out

Preparing fries takes time due to the 30-minute soak, as with my homemade chips. Cut your sticks in advance and submerge them in water in the fridge until ready to cook. Drying and oiling should be done at the last minute, just before placing the plate into the container.

Sweet potato fries lose their firmness quickly as they cool. Let them cool completely in the open air before closing the storage lid. A lid placed on hot fries traps steam and turns them into mush.

The next day, forget the microwave. Spread your portion on the crisper plate in the 1.4 L container, place the PowerPod on top and launch the Recrisp mode for 5 to 12 minutes, until the fries are piping hot. This drives out residual moisture and restores firmness to the caramelised ends.

What about you, what spice do you add to your sweet potato fries before cooking?

Frequently asked questions

Should I peel the sweet potato to make fries?

It is not mandatory. If you keep the skin, scrub it thoroughly under water before cutting. The skin adds a slight extra texture.

Can I use the 1.4 L container?

Yes, but only for a small amount. Place a maximum of 200 g of fresh fries with one teaspoon of oil. Allow 15 to 20 minutes in Air Fry, tossing 2 to 3 times.

My fries are black at the ends but hard inside, why?

Most often, the cut is uneven. Thin tips burn before the core of the larger pieces is cooked. Be sure to cut even-sized sticks of about 1.5 cm.