12 brats (about 1 lb.)
1 (12 oz.) can beer
3 tbsp. prepared mustard
1 lg. onion, peeled and sliced
2 tbsp. butter

Place all ingredients in large pan. Simmer about 10 minutes. Remove brats and grill until brown and firm to the tough - 25 to 30 minutes. Set pan with liquid on grill, add brats and simmer until ready to serve.