It is the combination of beans, grains, and a milk product that create the complete protein chain. So refried beans in a flour tortilla with cheese on it, or rice, beans, and cheese, is just as complete a protein as if you were to eat a meat based meal. DH and I aren't vegetarian but we have cut our meat consumption way back and don't feel like we are missing anything nutritionally. Often we will have something like mixed grains cooked with soy milk with yogurt on top for breakfast. Of course I we doctor it up with fruit, nuts, and spices.
Ann