01 - In a large skillet over medium heat, brown the ground beef until no longer pink, breaking it apart with a spatula as it cooks, about 5 minutes. Drain off any excess fat.
02 - Add the finely chopped onion, minced garlic, and diced jalapeño to the skillet. Sauté for 2 to 3 minutes until the vegetables are softened and fragrant.
03 - Stir in the chili powder, ground cumin, smoked paprika, salt, and pepper. Cook for 1 minute, stirring constantly, to toast the spices and release their full flavor.
04 - Fold in the drained diced tomatoes, diced green chilies, and drained black beans. Cook for 2 to 3 minutes until everything is heated through and well combined.
05 - Reduce the heat to low. Pour in the milk, then add the shredded cheddar and Monterey Jack cheeses. Stir continuously until the cheeses are fully melted and the mixture is smooth and creamy.
06 - Remove the skillet from the heat and gently fold in the sour cream until evenly incorporated for extra richness and creaminess.
07 - Transfer the hot dip to a serving bowl. Top with sliced green onions, chopped fresh cilantro, and additional jalapeño slices as desired.
08 - Serve immediately while hot alongside plenty of tortilla chips for dipping.