Preheat your oven to a gentle 180°F (82°C).

Pour 4 cups of heavy cream into a wide, shallow ovenproof dish, ensuring the cream is 1-2 inches deep.

Slide the dish into the preheated oven and let it bake undisturbed for 12 hours.

Allow the baked cream to cool completely at room temperature, which may take a few hours.

Cover the dish with plastic wrap or a lid and refrigerate it for at least 8 hours, or overnight if possible.

Carefully skim the thick, yellowish clotted cream off the top with a clean spoon or spatula.