Preheat oven to 350°.
Cook bacon in a large nonstick skillet over medium-high heat until crisp. Remove bacon from pan, reserving 1 tablespoon drippings in pan, and set bacon aside. Add onion to drippings in pan; sauté 3 minutes.
Combine bacon, onion, and remaining ingredients except cooking spray in a large bowl; toss well. Spoon the bean mixture into a 13 x 9-inch or 2 1/2-quart baking dish coated with cooking spray. Bake at 350° for 45 minutes.