2 pounds Yukon gold or red potato, cut into 1/4-inch slices
1 cup vegetable broth
½ teaspoon salt
2 cups shredded sharp Cheddar cheese, divided
3 tablespoons heavy cream
½ teaspoon garlic powder
¼ teaspoon ground black pepper
¼ teaspoon nutmeg
Set an oven rack about 6 inches from the heat source and preheat the oven’s broiler.
Combine potatoes, vegetable broth, and salt in a multi-functional pressure cooker (such as Instant Pot®). Close and lock the lid. Select high pressure according to manufacturer’s instructions; set timer for 1 minute. Allow 10 to 15 minutes for pressure to build.
Release pressure carefully using the quick-release method according to manufacturer’s instructions, about 5 minutes. Unlock and remove the lid.
Transfer potatoes carefully to an 8-inch square oven-safe deep dish. Combine 1 1/2 cups Cheddar cheese, cream, garlic powder, pepper, and nutmeg in the pressure cooker with the remaining liquid; select Saute function and cook until smooth and creamy, about 5 minutes. Pour sauce evenly over potatoes and sprinkle with remaining 1/2 cup Cheddar cheese.
Broil in the preheated oven until golden, about 5 minutes.