Spread a generous layer of butter on one side of each slice of bread. Sprinkle garlic powder and Italian seasoning on the buttered sides.

Place two slices of bread, buttered side down, onto a cutting board. Spread marinara sauce on the inner sides. Layer on mozzarella, parmesan, turkey pepperoni, and any additional toppings. Top with remaining slices, buttered side up.

Heat a skillet over medium-low heat. Carefully transfer the sandwich onto the skillet, cooking for about 3-4 minutes on one side, pressing down to crisp the bread and melt the cheese.

Flip the sandwich and cook for another 3-4 minutes, pressing down slightly to ensure even cooking.

Remove from skillet, let cool for a minute, then slice in half and garnish with fresh basil. Serve with extra marinara sauce for dipping.