Preheat the oven to 425 F. Make the panade by placing the cubed white bread, milk, mayonnaise, onion powder, garlic powder, Dijon mustard, dried oregano, dried basil, salt, and pepper into a small bowl. Mix everything together and then allow the panade to soak for 10 minutes to allow the bread to become fully saturated. It will be ready when it is mushy and paste-like.
Mix the minced turkey into the prepared panade, and then form the mixture into meatballs by scooping out a heaped tablespoon of the mixture and rolling it into a rough ball shape. Place the meatballs onto a baking paper-lined oven tray.
Bake the turkey meatballs in the oven for 20 minutes, until they are cooked through and lightly colored on top.
Meanwhile, make the tomato sauce. Start by heating a large, oven-proof pan to a medium heat. Add the olive oil and the diced onion, and then fry for 5 minutes. Then add the garlic and a pinch of garlic flakes, before cooking for another 2 to 3 minutes.
Add the can of chopped tomatoes to the pan along with the sugar and salt and pepper to taste. Allow everything to stew for 10 minutes or so until it has thickened.
Add the baked turkey meatballs to the pan with the tomato sauce. Add the torn mozzarella on top of the meatballs and then place the pan into the oven for 5 minutes, until the mozzarella is melted and coloring on top. Remove the pan from the oven and top with the chopped fresh basil. Serve straight away.