Things You'll Need
Soy powder, optional
Toaster oven, optional
Mochi is made by pounding hot, gelatinous rice until it forms a smooth, sticky ball. This is a long, laborious process typically reserved for special occasions, but you can purchase frozen mochi rice cakes in solid blocks. The two most common ways to cook frozen mochi rice cakes is in the microwave or in an oven or toaster oven. The mochi is often eaten plain or can be added to soups and stuffed with fillings similar to dumplings.
Wet all sides of the frozen mochi cake and place it on a microwave-safe plate. The water helps prevent the mochi from sticking to the plate as it cooks. Alternatively, you can line the plate with seaweed, soy powder or parchment paper to prevent sticking.
Microwave the frozen mochi cake for 1 minute.
Remove it from the microwave and test it with your fingers to see if it's hot. If it's not hot, return it to the microwave and cook in 30-second intervals until steaming hot.
Line a microwave-safe plate with parchment paper and set the frozen mochi on top. Make the parchment paper larger than the mochi cake so you can lift the edges of the paper later.
Microwave the mochi cake for about 30 seconds so it's partially cooked before placing it in the oven.
Lift the edges of the parchment paper and transfer the mochi cake to a baking tray. Preheat the oven or a toaster oven to about 375 degrees Fahrenheit.
Bake the mochi cake for about 5 minutes, checking it frequently to prevent burning. As it cooks, the mochi cake puffs up and the top begins to brown. Remove it from the oven after 5 minutes or when the top is medium golden brown.
The oven method is best if you prefer browned, crispy mochi, while microwaving is best if you prefer soft, stretchy mochi.
A toaster oven is most practical when only cooking one or two frozen mochi cakes, but a conventional oven works well for large batches, or if you don't have a toaster oven.