01 - If including meat, brown the ground beef or pork sausage in a skillet over medium heat until fully cooked through. Drain any excess fat and set aside.
02 - Add the cubed processed cheese, cubed cream cheese, and the entire can of Rotel diced tomatoes with green chilies (including juices) to 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 prevent sticking and ensure even melting, until all cheeses are fully melted and the mixture is smooth and creamy.
05 - Keep the slow cooker on the warm setting during serving. Offer alongside tortilla chips, crackers, or fresh vegetable sticks for dipping.