**Preheat the oven**
Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper or foil for easy cleanup.
**Prepare garlic butter**
In a small bowl, mix softened butter with minced garlic or garlic powder until well combined.
**Assemble the bread**
Place the bread halves cut-side up on the prepared baking sheet. Spread the garlic butter evenly over the surface of the bread. Next, spread an even layer of pesto on top of the garlic butter.
**Add cheese**
Sprinkle shredded mozzarella evenly over the pesto layer, then top with grated Parmesan.
**Bake**
Bake in the preheated oven for 10–12 minutes, or until the cheese is melted and bubbly. For extra browning, switch the oven to broil for 1–2 minutes, watching closely to avoid burning.
**Serve**
Remove the bread from the oven and let it cool for a minute. Slice into pieces and garnish with chopped parsley or basil if desired. Serve warm.