What is a marshmallow?Marshmallows are a popular dessert food item that are usually brown and sweet. The dessert is a soft and often fluffy item that is often used as a base layer in a recipe. The food is most commonly used in the United States and Canada but has recently become popular in other countries as well. In the United States, the dessert is most commonly baked as a cake or cookie and is often served as a dessert at a restaurant. The most common type of marshmallow is the one that is used in a cake or cookie but there are many other types of marshmallows that are used in different dishes.