01 - If using ground beef or sausage, heat a skillet over medium heat and cook the meat until fully browned, breaking it apart as it cooks. Drain off any excess fat and set aside.
02 - Transfer the cubed processed cheese, cubed cream cheese, and the entire can of Rotel diced tomatoes with green chilies (including juices) into the slow cooker. Add the cooked meat if using.
03 - Sprinkle the garlic powder and black pepper evenly over the contents of the slow cooker.
04 - Cover the slow cooker and cook on the low setting for 2 hours, stirring occasionally to ensure even melting and prevent the cheese from sticking to the sides.
05 - Once the dip is fully melted and smooth, set the slow cooker to the warm setting. Serve directly from the crockpot with tortilla chips, crackers, or fresh cut vegetables for dipping.