The word "topping" refers to something that is put on the top of another thing, usually to enhance its taste, appearance, or overall appeal. Full definition
Whatever it is, make a note of it in advance so you can stay of top of your tasks. (entrepreneur.com)
When the butter and chocolate have melted, remove the bowl from on top of the pot and stir in the sugar mixture with a wooden spoon. (strawberriesforsupper.com)
Spoon coconut cream (thick layer at top of can) into a large skillet; stir in curry paste. (myrecipes.com)