Preheat the oven to 350°F (175°C). Line a loaf pan with parchment or lightly oil it.

Heat a small skillet over medium heat with a drizzle of oil. Add the chopped onion and cook until soft and translucent, about 5 minutes. Add the garlic and cook for 30 seconds until fragrant. Remove from heat and let cool slightly.

In a large bowl, whisk the eggs with the milk, Worcestershire sauce, Dijon mustard, 1 cup ketchup, salt, pepper, and smoked paprika until smooth.

Add the breadcrumbs, cooled onion and garlic, and chopped parsley to the bowl. Crumble the ground beef into the mixture. Use your hands or a large spoon to mix gently until just combined. Avoid overworking the meat to keep the loaf tender.

Transfer the mixture into the prepared loaf pan. Press it down gently and shape it into a compact loaf.

Bake for 45 minutes.

While the meatloaf bakes, whisk together the glaze: 1/2 cup ketchup, brown sugar, Dijon mustard, Worcestershire sauce, and apple cider vinegar.

Remove the meatloaf from the oven. Spread the glaze evenly over the top. Return to the oven and bake another 10 to 15 minutes, until the glaze is set and an instant-read thermometer inserted into the center reads 160°F (71°C).

Let the meatloaf rest in the pan for 10 minutes before slicing to keep juices in the meat.