Instructions:
- Pat the beef cubes dry thoroughly with paper towels. In a large bowl, toss the beef cubes with the flour, salt, pepper, and paprika until lightly coated.
- Optional: Briefly sear the floured beef in batches in a hot, lightly oiled skillet until lightly browned on all sides. Transfer seared beef to the slow cooker insert.
- Place the sliced onions over the beef in the slow cooker.
- Gently melt the butter. In a separate bowl, whisk the melted butter into the beef broth, Worcestershire sauce, soy sauce, thyme, and rosemary until well combined.
- Stir the minced garlic into the liquid sauce mixture.
- Pour the entire garlic butter liquid mixture evenly over the beef and onions in the slow cooker.
- Cover the slow cooker. Cook on LOW for 6 to 8 hours or on HIGH for 3 to 4 hours, until the beef is fork-tender.
- Taste the sauce and adjust salt and pepper if necessary. If the sauce is too thin, remove the lid and cook on HIGH for the final 30 minutes.
- Garnish generously with fresh chopped parsley before serving over polenta or mashed potatoes.