1. Cut bacon crosswise into 1/4-inch strips. Melt butter in a large Dutch oven over medium heat; add bacon, and cook, stirring often, 8 minutes or until crisp. Drain bacon on paper towels, reserving drippings in skillet. Sauté onion in hot drippings 3 minutes or until onion is tender. Stir in bacon, ale, and next 3 ingredients; cook 3 minutes or until mixture is reduced by one-fourth.
2. Add collards, in batches, and cook, stirring occasionally, 5 minutes or until wilted. Reduce heat to medium-low; cover and cook 1 hour or to desired degree of doneness. Stir in vinegar, salt, and pepper.