1. Preheat oven to 350 degrees F.
2. Heat oil in medium-size saucepan over medium-low heat. Add the onion and garlic; saute for 5 minutes or until softened. Add both cans of beans; cook for 7 minutes. Slightly mash the mixture with a potato masher, leaving half the beans somewhat unmashed. Stir in corn.
3. Spoon an equal amount of bean mixture in the center of each tortilla. Top each with Cheddar cheese, dividing equally. Tuck in the sides of the tortillas; roll each tortilla into an egg-roll-shaped log. Place enchiladas in a 13 x 9 x 2-inch casserole. Pour the enchilada sauce over the top and around the sides of enchiladas. Cover with aluminum foil.
4. Bake in 350 degrees F oven for 35 minutes or until heated through.