Preheat oven to 350°F. Mist a 9-by-5-inch loaf pan with cooking spray.
Combine barbecue sauce, chipotles, adobo sauce, eggs, Worcestershire sauce, salt and pepper in a food processor and process until smooth. Transfer to a large bowl and add garlic, onion, beef and oats. Mix gently but thoroughly with your hands. Lightly pack mixture into loaf pan.
Bake for 45 minutes. Carefully spread ketchup on top and bake for 10 minutes longer, or until an instant-read thermometer inserted into center reaches 160ºF. Let stand for 5 to 10 minutes before slicing.