Pour Cream: Pour the heavy cream into a large, shallow ovenproof dish, ensuring the cream is about 1-2 inches deep.
Bake: Place the dish in the preheated oven and bake for 12 hours. The cream will form a thick, golden crust on top.
Cool: Remove the dish from the oven and allow it to cool to room temperature.
Chill: Cover the dish and refrigerate for at least 8 hours or overnight.
Separate Clotted Cream: Gently skim the thickened clotted cream from the top of the dish, leaving the liquid whey behind. Transfer the clotted cream to a jar or container.