Begin by seasoning the beef cubes with salt and pepper.
In a skillet over medium-high heat, sear the beef cubes until browned on all sides (about 5 minutes). This step adds extra flavor.
Transfer the seared beef to the slow cooker.
Add the chopped onion, minced garlic, sliced carrots, and mushrooms on top of the beef.
In a separate bowl, whisk together the beef broth, soy sauce, Worcestershire sauce, dried thyme, and smoked paprika. Pour this mixture over the contents in the slow cooker.
Stir everything gently to combine.
Cover the slow cooker and cook on low for 6-8 hours, or on high for 4 hours, until the beef is tender.
If you prefer a thicker sauce, mix cornstarch with a bit of cold water to create a slurry. About 30 minutes before serving, stir the slurry into the slow cooker and let it thicken up.
Taste and adjust seasoning with additional salt and pepper, if needed.
Serve the beef tips over rice, mashed potatoes, or noodles.
Notes
Garnish each serving with fresh parsley and serve with warm crusty bread.