Place a rack in the center of your oven and preheat to 425°F. Line a rimmed baking sheet with parchment paper.
Slice the bread in half lengthwise through its middle, as if you were slicing it into 2 giant slices of sandwich bread. Place on the baking sheet cut-sides up.
In a bowl, mash together the butter, garlic, Parmesan, 1 tablespoon parsley, garlic powder, and dsalt. Smear evenly all over the cut sides of the bread.
Place in the oven and bake until golden brown on the edges and its crisped to your liking, about 10 to 15 minutes. Let cool a few minutes, then cut crosswise into slices.
Notes
TO MAKE AHEAD: After slathering the bread with the garlic butter, place the baking sheet in the freezer and freeze just until the butter is solid. Then, wrap the garlic bread tightly in plastic wrap followed by foil. Freeze for up to 2 months. You can bake it directly from frozen, just adding a few extra minutes to the cooking time.
TO STORE: Wrap the garlic bread in foil or transfer it to an airtight container. Store it at room temperature for 2 to 3 days.
TO REHEAT: Warm up leftover garlic bread wrapped in foil in a 350ºF oven until it’s heated through. You can warm it in the microwave if that’s your only option, but it may end up tough.
TO FREEZE: If you want to freeze baked garlic bread, store it in a freezer bag or airtight container for up to 2 months. You can reheat it directly from frozen or thaw it at room temperature first for faster reheating.