Combine the millet, water and vegetable stock in a pot, and bring to a boil.

Reduce heat to low, cover, and simmer for 15 minutes, or until the water is absorbed.

Slice the tops off of the peppers, and remove the seeds and cores. Set aside.

When the millet is done, stir in the tomatoes and black beans. Spoon into the peppers until filled. Place the peppers into a baking dish

Cook until peppers are tender. Turn peppers every 2 to 3 minutes to ensure even cooking.

Optional - add cheese on top near the end of the cooking time