You may come across recipes where you are asked to melt chocolate, cheese or butter in a double boiler.
U need not go and purchase a new kitchen item for this. A milk cooker will do the job. Even if you dont have a milk cooker just heat water in a big pan and place a preferably thick walled utensil in this and use it as a double boiler. The advantage with this arrangemnet is u will be able to use utensils of any size depending on the quantity of cooking