Preheat the oven to 375°F (190°C). Line a quarter sheet pan with foil or parchment paper.
Make the panade. In a large mixing bowl, combine breadcrumbs and milk. Stir and let sit 5 minutes until it forms a thick paste. This is the secret to a moist, tender meatloaf.
Add the aromatics. To the soaked panade, add diced onion, minced garlic, egg, Worcestershire, Dijon, salt, pepper, Italian seasoning, and smoked paprika. Whisk until evenly combined.
Mix in the beef gently. Add ground beef and mix with your hands or a fork just until combined. Do not overmix — this is the second biggest cause of tough meatloaf.
Shape the loaf. Turn the mixture onto the prepared sheet pan and shape into a free-form loaf about 8 inches long, 4 inches wide, and 2 inches tall.
Bake for 25 minutes. While baking, whisk together all glaze ingredients in a small bowl until smooth.
Glaze and finish baking. After 25 minutes, brush two-thirds of the glaze over the top and sides. Return to oven for 15 to 20 more minutes, until an instant-read thermometer reads 155°F (68°C).
Rest and slice. Remove from oven, brush on remaining glaze, and rest 10 minutes (internal temp will climb to a safe 160°F). Slice into 1-inch slices and serve.