Add raw ground beef to the bottom of your slow cooker.
Sprinkle in chopped onion, garlic, taco seasoning, and salt/pepper.
Pour in tomato sauce and broth (and green chilies or salsa if using).
Stir gently to combine. Don’t worry if it’s not fully mixed yet.
Cover and cook on LOW for 5–6 hours or HIGH for 2.5–3 hours.
Once cooked, stir well and break up the beef with a spoon or spatula.
If too liquidy, cook uncovered for 15–20 minutes on HIGH to reduce moisture.
Taste, adjust seasoning if needed, and serve!