Preheat your oven to 400°F (200°C).
Arrange the garlic bread loaves on a baking tray with the cut sides facing up.
Evenly distribute the marinara sauce over each loaf, ensuring every corner is covered.
Generously layer the grated mozzarella cheese atop the sauce.
Add the diced salami and chopped zucchini for a burst of flavor.
Sprinkle the Italian seasoning, onion powder, and optional chili flakes over the entire surface.
Place the tray in the oven and bake for about 12-15 minutes, or until the cheese is bubbling and the edges of the garlic bread are perfectly crisp.
Once done, take them out and allow them to cool slightly.
Finish with a sprinkle of fresh parsley before slicing into portions and serving warm.