Remove the refrigerated pie crust from the fridge 15 minutes before starting.
Unroll the crust, set the tart pan on top, and cut a circle about 1 inch wider than the pan.
Press the crust into the tart pan, tucking down the sides. Trim so the crust is level with the top edge.
Place the tart pan in the air fryer basket and cook at 300°F for 5 minutes to par-bake the crust.
Sprinkle the grated cheese over the base of the par-baked crust, then add the cooked vegetables.
Whisk the egg whites and heavy cream together until smooth and slightly frothy.
Pour the egg mixture over the filling, stopping level with the top edge of the crust. Do not overfill. Season with salt and pepper.
Return to the air fryer basket and cook at 300°F for 8 to 10 minutes, until the center is set and no longer wobbles.
Rest 1 to 2 minutes, then push the removable bottom up to release the quiche. Slide a spatula underneath to lift it off the base plate.