1. Preheat the oven to 350F
2. Over medium-low heat, melt the butter in a small-sized skillet. Spray the pan with nonstick cooking spray. Cook, occasionally stirring, for 6 minutes or until the onion is soft. Allow cooling slightly after removing from the heat. Gently stir the onion, three tablespoons of ketchup, and the remaining ingredients in a mixing dish.
3. Shape the meat mixture into an eight × 4-inch loaf on a baking sheet covered with cooking spray. Brush the remaining three tablespoons of ketchup over the top of the loaf. At 350°F, bake for 35 minutes, or until a thermometer reads 160°F. Allow it to sit for 10 minutes before cutting into eight slices.

This delicious meatloaf recipe can suffice for four people at two slices each. Check out this video recipe for more interesting ways to enjoy meatloaf recipes.