Heat the oven to 400 degrees F. Line a large baking sheet with parchment paper.
In a large bowl, combine the ground turkey, breadcrumbs, egg, onion, garlic, rosemary, salt, and pepper. Mix until just blended, then shape into a loaf and place in the center of the baking sheet.
In a separate bowl, toss the carrots and potatoes with 2 tablespoons olive oil. Spread the vegetables around the meatloaf on the baking sheet.
Bake for 45 minutes, or until the meatloaf reaches 165 degrees F inside and the vegetables are tender.
Remove the pan from the oven and transfer the meatloaf and vegetables to a serving platter. Reserve the pan drippings.
Place the baking sheet over medium heat on the stovetop or pour the drippings into a small saucepan. Add the remaining tablespoon of olive oil and the flour. Cook for 1 minute, stirring constantly.
Slowly whisk in the chicken broth and simmer for 3 to 4 minutes until the gravy thickens. Season with a pinch of salt and pepper if needed, then serve over the sliced meatloaf and vegetables.