Wild Rice and Cheese Casserole

4 C boiling water
1 C brown rice
1 C wild rice
1 large onion, chopped
14-oz can small black olives
1 green pepper, chopped
1 C chopped walnuts
4 C grated Cheddar or Colby cheese
4 C sliced mushrooms
1/2 stick butter (4 T)

Preheat oven to 350 F. Pour the boiling water into a large rectangular baking dish. Add the brown and wild rice and bake for 20 minutes. Meanwhile, prepare the remaining ingredients.

Remove the rice and stir in the butter, then the rest of the ingredients. Cover and bake for 20 more minutes. Serves 8.