Preheat your oven to 350°F (175°C) and gather all ingredients.
In a large mixing bowl, combine the ground beef, chopped onion, taco seasoning, pepper Jack cheese, and crushed tortilla chips, mixing well to evenly distribute ingredients.
In a separate bowl, whisk together the eggs, milk, and ¼ cup of taco sauce until smooth.
Pour the egg mixture into the beef mixture, stirring thoroughly until all components are incorporated.
Transfer the mixture into a 9x5x3-inch loaf pan, pressing it down to evenly fill the pan. Pour an additional strip of taco sauce along the center of the loaf.
Bake in the preheated oven for 45 to 60 minutes, or until the meatloaf is thoroughly cooked and golden brown on top. Use an instant-read thermometer to ensure the internal temperature reaches at least 160°F (72°C).
Slice, serve, and enjoy this Mexican-inspired comfort dish!