Cheesy Rice and Beans

Saute 1/2 chopped large yellow onion with 1 chopped tomato in olive oil.  Add 1-2 cups rice of any kind, salt and pepper, and mix.  Put mixture in a mixing bowl.  Heat up 1 can of pinto beans, rinsed off.  Add to the mixing bowl.  Add 1/2 cup grated cheddar.  Mix until the cheese melts.  Serve it up to the kids.