Brown the ground beef and diced onion in a skillet over medium heat until the beef is fully cooked and the onion is tender.
Drain any excess fat from the skillet and transfer the beef and onion mixture to a slow cooker.
Add the cubed processed cheese and cream cheese.
Add the diced jalapeño, salsa, green chilies, and hot sauce.
Stir the ingredients gently to distribute everything evenly.
Cover and cook on LOW for about 3 hours, stirring halfway through.
Once the cheese is completely melted and the dip is smooth, stir thoroughly.
Keep the dip warm in the slow cooker and serve with tortilla chips.
For the best texture, give the slow cooker queso beef dip a final stir immediately before serving.