Make sure the oven rack is in the center position and preheat the oven to 375 degrees F.
Wash your hands and place the turkey in a large mixing bowl. Add the onion, bread crumbs, celery, bell pepper, egg, 1 tablespoon of the ketchup, the garlic, Baby Bam, salt, and ground pepper, and mix with your hands until the ingredients are well incorporated.
Transfer the turkey mixture to a 1-pound loaf pan and use your hands to form it into a loaf shape. Wash your hands really well with warm, soapy water before proceeding.
Pour the remaining 3 tablespoons of ketchup on the turkey and smear evenly over the top with the back of a spoon.
Bake until brown on top, cooked through, and an instant-read thermometer inserted into the center reaches 165 degrees F, about 45 to 50 minutes.
Using oven mitts or pot holders, remove the loaf from the oven and let rest for 5 minutes before serving.
Yield: 6 servings