Add the beef stock to the slow cooker and stir to combine. Cover the Crockpot and cook on high for 4 hours or low for 8 hours.
1 1/2 cups beef stock
In a small bowl, combine the cornstarch with 3 tablespoons of water. Mix well and then stir into the Crockpot. Continue to cook, uncovered, for 10-15 minutes or until sauce is slightly thickened. Garnish with parsley before serving.
3 tablespoons cornstarch, 1/4 cup finely chopped fresh parsley
Notes
Searing the beef is optional but recommended. If your slow cooker offers a sauté function, you can sear the beef directly in the slow cooker.
You can replace the onion powder, garlic powder, and dried thyme with one package of onion soup mix, if preferred.
Store leftover slow cooker beef tips and gravy in an airtight container in the refrigerator for up to 2 days. Reheat thoroughly on the stove or in the microwave.