Preheat oven to 275 degrees.
Heat butter in large skillet over medium-high heat.
Dredge meat in flour and brown quickly on both sides. Remove meat and set aside. Add onion to skillet and saute until softened. Remove half of onions and spread remaining onions evenly in skillet. Place meat on top of onions in skillet and top with reserved onions. Pour in beer and add bouquet garni and salt and pepper to taste. Cover and bake 2 hours until fork tender. Remove bouquet garni before serving.