Preheat the oven to 375 degrees and line a loaf pan with parchment paper.
In a large bowl, combine the ground beef, breadcrumbs, egg, onion, garlic, 1/4 cup of the cranberry sauce, 1 tablespoon of the balsamic vinegar, 1 tablespoon of the rosemary, salt, and pepper.
Mix the ingredients with your hands until evenly combined, then press the mixture into the prepared loaf pan.
In a small bowl, stir together the remaining 1/4 cup cranberry sauce, remaining 2 tablespoons balsamic vinegar, and remaining 1 tablespoon rosemary to make the glaze.
Bake the meatloaf for 35 minutes, then remove it from the oven and spread the glaze evenly over the top.
Return the meatloaf to the oven and bake for 15 more minutes, or until the internal temperature reaches 160 degrees.
Let the meatloaf rest for 5 minutes before slicing and serving.