In a food processor, add onion, jalapeno, garlic, and a handful of cilantro. Pulse until finely chopped.
Preheat oven to 400 degrees F. In a small cup, mix together crushed corn chips and milk. Let sit for five minutes. In a medium bowl combine beef, onion mixture, corn chip mixture, eggs, salt, and pepper. Mix together well with your hands.
Shape mixture into about 35 medium-sized meatballs (about 2 tablespoons per meatball). Roll them into balls and place them on greased baking sheets. Bake meatballs for 12-15 minutes until they are cooked through and browned.
Transfer baked meatballs to a large pot with enchilada sauce and chicken stock. Simmer meatballs for about 20 minutes on low heat, stirring occasionally. Season with salt and pepper to taste.
Meanwhile, mix together quick salsa topping.
Serve tacos by spooning some sour cream onto a corn tortilla and topping it with a 2-3 meatballs and some sauce. Top with quick salsa and cotija cheese. YUM.
This meal freezes fantastically. Freeze meatballs in freezer safe bags once they are cooled. Thaw on stove top over medium-low heat.