Tempeh is a traditional Indonesian food. It is a fermented food made by the controlled fermentation of cooked soybeans with a Rhizopus mold. The tempeh fermentation by the Rhizopus mold binds the soybeans into a compact white cake. People can cook tempeh in a variety of ways, but most Indonesians bake it with a little oil and salt like in this recipe. Tempeh is a great source of protein.