Preheat the oven to 375°F (190°C). Line a baking sheet with parchment paper or foil for easy cleanup.
Slice the loaf of bread lengthwise and place both halves cut-side up on the prepared baking sheet.
In a small bowl, mix the softened butter, olive oil, minced garlic, parsley, salt, and black pepper until evenly combined.
Spread the garlic butter mixture evenly over the cut surfaces of the bread, making sure to cover all edges.
Sprinkle grated parmesan cheese evenly over the top if using.
Bake in the oven for 10–12 minutes until the edges turn golden and the butter is fully melted.
For extra crispiness, broil for 1–2 minutes until the top becomes lightly toasted and fragrant. Watch closely to prevent burning.
Remove from the oven, let cool for 1 minute, then slice into serving pieces and serve warm.