This is a two tiered utensil, wherein the top section is perforated at the base and sometimes the sides. This fits over the lower section, and has a lid that fits snugly. A nozzle for letting out excess steam is provided in some form on the lid. When used, the steam coming up from the boiling water underneath cooks the preparation place in the perforated section. It may be made of steel,copper, brass, nonstick ware, or even cane as in chinese tradition. The only care to be taken is to be careful that the right amount of water is poured into the vessel, since too much will make it rise into the food, making it mushy, and too little will burn the utensil.
Boiling Pan :
Bhagola, pathila or thapela in hindi. These are very deep with vertical walls, and may or may not have handles. These pans are mainly used to boil vegetables, etc. with plenty of water, or to cook dals, etc. which need to be cooked covered, and water content is quite a bit. One can boil in these vessels adding more water as required.