Substitute for whipped topping?
You could whip your own cream. Use 1/3 of the amount of heavy cream as cool whip, and whip with a splash of vanilla extract and a pinch of sugar to taste, either by hand or with a mixer. If a recipe calls for 1 cup of "whipped topping", you would start with 1/3 cup of heavy cream which whips up to 1 cup.