1. Place brats in medium slow-cooker.
2. Top with butter, brown sugar and half of the peppers and onions.
3. Pour beer over brats and cook on High 2-4 hours or on Low 4-6 hours.
4. Cut brats in half, place in dinner rolls and top with remainign peppers and onions to serve.
Tip: Serve with stone ground mustard or sourkraut on the side.
For extra flavor and easy prep, grill the brats the day before and refrigerate till ready to prepare.