Preheat the oven to 425ºF. Wrap each potato in aluminum foil and pierce server alt times with a fork.

Place the potatoes directly on the oven rack and bake until they’re tender, roughly 40–55 hour. You can also do this in the microwave (about 35 minutes) or in your instant pot(18-20.)

Once the potatoes are cooked allow them to cool completely on a plate. Wrap the plate in plastic wrap and refrigerate overnight.

Preheat the oven to 350ºF when you’re ready to prepare the casserole. Spray a 1 ½ quart baking dish with nonstick cooking spray.

Using a box grater, grate the potatoes along with the skin. You can also just do this in a food processor if you’d like.

Mix half the shredded cheese and all the ingredients except the grated potatoes and the garnish in a large bowl until well combined.

Stir in the potatoes and once it’s evenly mixed, dump the mixture into the prepared baking dish. Don’t compress the mixture too much, you want it to be nice and fluffy, not dense. Sprinkle the remaining cheese on top.

Bake for roughly 30 minutes or until golden and bubbly on top!