Prepare the casseroles by filling hot water (for hot food) or cold water (for cold food). Empty the water and immediately fill it with the prepared food. For hot food, let the initial steam come out and then cover the lid to the casserole. Do not separate the stainless steel bowl from the main body of casserole. Keep it away from an open flame or electric hot plate or gas stove and even direct heat, etc. When storing hot food, do not cover and lock the lid, if the food is at boiling temperature. Cover and lock the lid only if the food temperature is below 80 Degree C. If the lid is covered and locked with the food at boiling temperature, there is a possibility that the lid cannot be opened for a very long time due to the expansion of the intense steam created from the extremely high temperature in the container. It may also damage the container if this instruction is not followed. Wash the container by hand with a mild soap. Before initial use, clean the product thoroughly.