If cooking your own pinto and black beans, cook until firm-tender and not mushy. Combine pinto beans, black beansm garbanzo beans, green beans and wax beans in a large bowl. Add green pepper and red onion. In a small bowl, mix oil, vinegar, salt, oregano, garlic powder and black pepper to taste. Pour over salad and toss gently but thoroughly. Cover and refrigerate overnight. Just before serving, add tomatoes and mayonnaise. Toss until well blended.
Makes 6 to 8 servings.
From: MEXICAN COOKERY by Barbara Hansen, HP Books, Tucson, 1980. ISBN 0-89586-038-4 Shared by: Karin Brewer, Cooking Echo, 5/93