Chili Con Queso - cooking recipe

Ingredients

1 medium onion, firmly chopped
2 Tbsp. butter
8 oz. can tomatoes, chopped
1 to 3 serrano chilies
3 c. grated Jack or Cheddar cheese
1/2 c. sour cream

Preparation

Fry the onion gently in the butter until it is translucent. Add the tomatoes and chili peppers; simmer, stirring frequently, until thickened.
Add the cheese, stirring as you do.
Cook, stirring constantly, until the cheese melts.
For a thinner dip, add the cream.