Chili Spaghetti

3/4 lb lean ground beef
1 small onion
1 clove garlic
14 ounces dry spaghetti, cooked
4 cups tomato sauce
4 ounces lowfat cheddar cheese, shredded
1 jar small pimientos
1 teaspoon chili powder
pinch salt
1/8 teaspoon pepper

Sauté meat, onion and garlic in skillet till meat is cooked. Drain well. Add remaining ingredients except cheese and simmer 10 minutes. Add cheese and cook till melted.