Saute onions in oil until translucent, add beef and taco seasoning according to taco seasoning directions, brown. Stir in refried beans; heat to warm, add olives.
Warm enchilada sauce in saucepan. Dip each tortilla into the sauce. Fill each with about 1/4 cup bean mixture, roll to enclose. Arrange rolls, seam side down, in a 13 x 9 x 2 inch baking dish.
Pour remaining sauce over rolls. Sprinkle with cheese. Bake in a 350 degree oven for 25 minutes or until heated through. Makes 6 servings.