Marshmallow creme is smooth and spreadable, especially when compared to whole marshmallows, but it is still far too thick and sticky to be used as an ice cream topping. Marshmallow sauce for ice cream should be runny enough to drizzle or pour as you would with a caramel sauce or chocolate sauce. You can make marshmallow sauce to top ice cream or just buy a jar of marshmallow creme from the grocery store. For best results, make the marshmallow sauce immediately before using it.
Scoop the marshmallow creme -- either homemade or store-bought -- into a microwave-safe bowl.
Add water to the marshmallow creme and mix it in as much as possible. Don't expect to stir the water in easily; break up the marshmallow creme with a fork to incorporate the water. Use about a tablespoon of water for each heaping tablespoon of marshmallow creme.
Microwave the marshmallow creme and water on high for 15 seconds. Remove it from the microwave and stir well. If the marshmallow sauce isn't smooth after 15 seconds, microwave it in 10-second intervals, stirring in between, until you achieve a consistency similar to caramel sauce.
- Store leftover marshmallow creme sauce in an airtight container in the refrigerator for long-term storage. You may need to reheat and stir it to make it smooth again. Marshmallow creme is mostly made of sugar, which has a very long shelf life. The addition of water to make a sauce will not shorten its life.