2 medium-size onions, chopped
2 cloves garlic, minced or pressed
2 teaspoons salad oil
2 cans (15 ounces each) pinto or other beans
2 tablespoons cider vinegar
1/8 teaspoon ground red pepper (cayenne)
Salt
Cumin, to taste

In wide nonstick frying pan, combine onions, garlic, oil and 1 tablespoon water. Cook over medium heat, stirring often, until mixture is deep golden (20-30 minutes). If onions stick to pan bottom or pan appears dry, add a little more water, one tablespoon at a time. Drain beans, reserving 1/2 cup of the liquid from cans. Add beans to pan with 1/2 cup reserved liquid, vinegar, and red pepper. Coarsely mash beans with a spoon. Season to taste with salt and cumin, if desired. Heat until steaming.