Preheat oven to 400 degrees.
Wash the peppers, cut off the top and hollow out the inside.
Cook couscous according to package directions.
In a bowl combine cooked couscous with beans, tomatoes, onions, salt, pepper and cheese.
Spoon mixture into peppers.
Place peppers in a casserole dish and cover.
Bake for 45 minutes or until peppers are soft when pierced with a fork.