Appetizers, Side Dishes, Soups

Sweet Potato Gratin

Cooking method:

Ninja® Foodi™ 8-qt. 9-in-1 Deluxe XL Pressure Cooker & Air Fryer
  • Prep time: 5 mins
  • Total time: 20 mins
  • Skill easy
  • Serves 6 people

Sweet Potato Gratin

TIP:  although the sweetness of the sweet potatoes helps accentuate the flavors of the dish, the gratin can be made with any potato you’d like to use.  


Tip: Allergy Advice

This dish contains the following allergens: Dairy, Nuts, Wheat


  • 2 tablespoons unsalted butter
  • 3 tablespoons all-purpose flour
  • 2 cups heavy cream, warmed in the microwave
  • 2 teaspoons kosher salt
  • 1 teaspoon pumpkin pie spice
  • 1/4 cup water
  • 3 large sweet potatoes, peeled and cut in half, then cut into half-moons 1/4 inch (5/8 cm) thick
  • 1 1/4 cups shredded cheddar cheese, divided
  • 1/2 cup chopped walnuts or pecans, or slivered almonds

Cooking mode

When entering cooking mode - We will enable your screen to stay ‘always on’ to avoid any unnecessary interruptions while you cook!


  • Step 1

    Select SEAR/SAUTE and set to MD:HI. Select START/STOP to begin. Let preheat for 5 minutes. 

  • Step 2

    Add the butter. Once melted, add the flour and stir together until a thick paste forms, about one minute. (The combination of butter and flour is called a Roux). Continue cooking the rule for two minutes, stirring frequently with a rubber-coated whisk. Slowly add the warm cream while continuously whisking so there are no lumps, about 3 minutes. The cream should be thickened.

  • Step 3

     Add the salt and pumpkin pie spice and whisk to incorporate. Whisk in the water and let the mixture simmer for 3 minutes.

  • Step 4

    Place the potatoes in the pot. Assemble the pressure lid, make sure the pressure release valve is in the SEAL position.

  • Step 5

    Select PRESSURE and set to LO. Set time to 1 minute. Select START/STOP to begin. 

  • Step 6

    When pressure cooking is complete, quick-release pressure by moving the pressure release valve to the VENT position. Carefully remove lead when the unit has finished releasing pressure. 

  • Step 7

    Add 1/4 cup of cheese and stir gently to incorporate, being careful not to break up the cooked potatoes. Ensure mixture is flat, then cover top with remaining one cup of cheese. Sprinkle the nuts over the cheese. Close crisping lid. 

  • Step 8

    Select BROIL and set time to 5 minutes. Select START/STOP to begin.    

  • Step 9

    When cooking is complete, open lid and let the gratin cool for 10 minutes before serving.