Preheat the oven to 375°F and line a loaf pan with parchment paper.
In a large bowl, combine the ground beef, breadcrumbs, egg, onion, salt, and pepper.
Add half the blueberries, 2 tablespoons brown sugar, and 2 tablespoons maple syrup. Mix gently until just combined.
Press the mixture into the prepared loaf pan and smooth the top.
In a small bowl, stir together the remaining brown sugar and maple syrup. Fold in the rest of the blueberries.
Spread the glaze evenly over the meatloaf.
Bake for 50 to 55 minutes until the internal temperature reaches 160°F.
Let the meatloaf rest for 10 minutes before slicing. Garnish with extra blueberries.