Heat the oven to 350°F and line a rimmed baking sheet with parchment.
In a large bowl, combine the ground beef, breadcrumbs, egg, milk, onion, 1 tablespoon hickory liquid smoke, smoked paprika, salt, and pepper. Mix with your hands until the mixture just holds together.
Shape the meat into a loaf about 8 inches long and place it on the prepared baking sheet.
Bake for 30 minutes.
While the meatloaf bakes, stir together the brown sugar, ketchup, and Dijon mustard in a small bowl.
Remove the meatloaf from the oven and spread the glaze evenly over the top and sides.
Return the meatloaf to the oven and bake 20 to 25 minutes more, until the internal temperature reaches 160°F.
Let the meatloaf rest 5 minutes before slicing.