Chile con Queso Dip

2 tablespoons butter
1 medium yellow onion, finely chopped
1 small can jalapeno peppers, chopped
2 cups canned chopped tomatoes
1 small jar pimiento peppers, chopped, drained
3/4 cup cheddar cheese, grated
salt and pepper, to taste

Saute onion in butter in medium saucepan. Combine onions with jalapeno peppers, tomatoes, and pimiento in crock pot. Heat; let simmer for 10 - 15 minutes to meld the flavors. Add cheddar cheese, mixing thoroughly until melted.