The main ingredient used in marshmallows is sugar. Traditional marshmallows are made from a mixture of sugar, water, and gelatin, which gives them their unique spongy texture. The sugar is dissolved and combined with the gelatin to create a syrup that is whipped until it becomes fluffy. This mixture is then cooled and set into a soft, chewy confection that is often flavored with vanilla. Marshmallows are popular treats on their own and are commonly used in desserts like s'mores, rice cereal treats, and hot chocolate fluffiness.