Cooking Instrucitons. Add 1/2 lb of dry silkworm food into a cooking pot containing 3 cups of hot tap water (bottled water is best). Thoroughly mix with a whisk or hand mixer until you get a consistency similar to cake batter. Bring water to a boil for 5 minutes (stir continuously). Carefully(!) pour the food into a container for storage. We recommend a 1" deep cookie sheet. Immediately place a sheet of plastic wrap over the food and allow to cool. Once cooled, place the sheet into the refrigerator to completely cool and firm up. Once firm, we recommend cutting the food into 2" squares (like brownies) and bag them in separate baggies for storage. Depending on how many silkworms you're feeding, and how big they are, you can either place an entire square in with them (lots of bigger worms), or you can careful grate a square over babies with a cheese grater.