Preheat the oven to 350°F. Line a small sheet pan with foil or parchment paper. Grease the tray with olive oil or nonstick spray.

Heat a small skillet over medium heat. Add the olive oil, then the onions and ½ teaspoon of salt. Cook, stirring frequently, until softened, about 6 minutes. Add the garlic and cook for one more minute. Transfer the mixture to a large mixing bowl and let cool until just warm, about 15 minutes.

Once the onion mixture has cooled, add the ground beef, eggs, milk, Panko, ketchup, Worcestershire sauce, Italian seasoning, remaining 1 teaspoon of salt, and pepper. Mix gently but thoroughly to combine.

Gather the mixture together and place it on the prepared baking sheet. Form into a rectangular shape that is 8x4x2-inches. Bake for 30 minutes.

In a small bowl, stir together the ketchup, brown sugar, and Worcestershire sauce until combined.

Brush half of the sauce evenly over the meatloaf. Return to the oven and bake until a thermometer inserted in the center registers 160°F, 20 to 25 minutes. Brush the remaining sauce over top. Let rest 10 minutes before slicing.