Preheat oven to 350 degrees F and line a rimmed baking sheet with foil, set aside.
In a large bowl add ground beef, cubed bread, eggs, milk, chopped onion, chopped celery, Worcestershire sauce, kosher salt, poultry seasoning, and black pepper.
Using your hands, mix all the ingredients together until well combined. Because the meat is cold I usually have to take a few breaks to warm my hands up while mixing. You can also use a silicone spatula BUT I think it gets better mixed by hand.
Once your meat is mixed place it on the baking sheet and form into a loaf. I usually make my loaf about 6 inches wide by 12 inches long.
Add to the preheated oven and bake for 45 minutes.
While the meatloaf bakes mix together ketchup, dark brown sugar, and light Karo syrup.
After an hour of baking remove the meatloaf, top with ketchup mixture, and place back into the oven.
Cook for another 15 minutes or until the meatloaf is fully cooked (it should feel firm) and the ketchup mixture on the top has started to bubble.
Remove from the oven, let rest for 5 minutes, slice, and enjoy.