Preheat oven to 400 degrees.

Combine tomato sauce, barbecue sauce and sugar in a small saucepan over medium heat. Heat until bubbling, stirring constantly, and remove from heat.

Add all but 2 Tablespoons of this mixture to the ground beef in a large mixing bowl, along with the flour, salt, onion powder, garlic powder and ground pepper. Mix until well combined.

Place mixture in a loaf pan. Wrap tightly with foil and bake 30 minutes.

Using a spatula to hold the meatloaf in the pan, drain the fat.

While still in the pan, slice the meatloaf into 8 slices. Pour remaining sauce over the top of the meatloaf, in a stream down the center.

Return the sliced meatloaf to the oven, and bake uncovered for an additional 30 minutes.

Allow to cool for 5-10 minutes before serving.