- Preheat oven to 375° F. Line a rimmed baking sheet with aluminum foil. Grease the foil with olive oil or spray with cooking spray. 
- Heat the 1 tablespoon olive oil in a skillet over medium heat. Add the onion and cook until softened, 3-4 minutes. Add the garlic and cook, stirring, for 30 seconds. Remove pan from the heat. 
- In a large bowl, combine the egg, ketchup, Worcestershire sauce, Italian seasoning, garlic powder, salt and pepper. Stir until the ingredients are well combined. 
- Stir in the sautéed onion and garlic. 
- Add the breadcrumbs and ground turkey. Mix with your hands until everything is just combined; do not overmix. 
- Transfer the meat mixture to prepared baking sheet and use your hands to shape it into a loaf shape, about 6 inches long, 4½ inches wide and 1½ inches tall. 
- In a small bowl, whisk together the glaze ingredients: ketchup, brown sugar and apple cider vinegar. Brush the glaze over the top of the meatloaf.  
- Bake for 45-60 minutes, until the internal temperature in the center of the meatloaf registers at least 165° F on an instant read thermometer. Let the meatloaf rest for 10 minutes. Then transfer to a serving platter or cutting board, slice and serve.