1 tablespoon butter

½ cup chopped onions

1 tablespoon all-purpose flour

2 cups milk 

1 teaspoon ground cumin

1 teaspoon salt

1/8 teaspoon ground red pepper (cayenne)

1 can (15 ounces) black beans, drained, rinsed

1 can (11 ounces) corn with red and green peppers, drained

Melt butter in 2 quart saucepan over medium heat.  Add onions. Cook, stirring occasionally, until soft.  Reduce heat to low.  Add flour.  Cook for 1 minute stirring constantly.  Slowly add milk.  Cook until sauce starts to thicken.   Stir in cumin, salt and ground red pepper. Stir in black beans and corn.  Cook until heated through.  Stir in cheese; cook until melted.