Preheat the oven to 350 degrees. In a large mixing bowl, combine the ground beef, shredded cheddar cheese, diced jalapeños, breadcrumbs, egg, milk, chopped onion, minced garlic, salt, and black pepper. Mix until just combined.
Shape the mixture into a loaf and place it in a loaf pan or on a lined baking sheet.
Bake for 45 minutes.
While the meatloaf bakes, stir together the ketchup, brown sugar, yellow mustard, and Worcestershire sauce in a small bowl to make the glaze.
Remove the meatloaf from the oven and spread the glaze evenly over the top. Return it to the oven and bake for 15 more minutes until the glaze thickens and the internal temperature reaches 160 degrees.
Let the meatloaf rest for 5 minutes before slicing.