In a large bowl, combine ground beef, egg, cheddar, taco seasoning, onion powder, salt, and pepper. Mix well.
Form into 15 meatballs and place on a foil-lined baking sheet.
Bake meatballs for 25 minutes or until cooked through.
Reduce oven to 350°F (175°C). Pour 1/4 cup enchilada sauce into a small baking dish or cast iron skillet.
Add cooked meatballs, top with more enchilada sauce and shredded cheddar.
Bake for 15 minutes until cheese is melted and bubbly. Serve warm.
Notes
Use freshly shredded cheese for best flavor. You can prep meatballs ahead of time for a quicker bake. For extra heat, add jalapeños or hot sauce before baking.