- 1/4 cup butter
- 4 large onions, thinly sliced
- 4 cups beef broth
- 1 clove garlic, minced
- salt and ground black pepper, to taste
- Melt butter in a skillet over medium heat. Cook and stir onions in melted butter until clear and browned, 10 to 15 minutes; transfer to a slow cooker. Add beef broth, garlic, salt, and black pepper to the slow cooker.
- Cook on High for 4 hours or on Low for 8 hours.