Cook the Ground Beef: In a skillet over medium heat, cook the ground beef with the diced onion until the meat is browned and the onions are soft, about 5-7 minutes. Drain any excess fat.
Add Garlic: Add the minced garlic to the skillet and cook for another minute, until fragrant. Remove from heat.
Transfer to Slow Cooker: Transfer the cooked beef and onion mixture to the slow cooker. Add the can of diced tomatoes with green chilies (undrained), cream cheese, and sour cream.
Add Seasonings: Stir in the shredded cheddar cheese, chili powder, cumin, salt, and pepper. Mix everything until well combined.
Cook: Cover the slow cooker and cook on low for 2-3 hours, or until the dip is hot and the cheese has melted. Stir halfway through cooking to ensure even melting.
Serve: Once the dip is fully melted and creamy, stir to combine, and serve immediately with tortilla chips, crackers, or fresh veggies for dipping.
