Preheat your oven to 375°F (190°C). If using a baguette, slice it in half lengthwise for classic pull-apart garlic bread, or slice into 1-inch thick diagonal pieces for individual portions. Place the sliced bread cut-side up on a baking sheet lined with parchment paper or foil.

Make garlic butter

In a small bowl, combine the softened unsalted butter and olive oil. Add the minced garlic, finely chopped parsley, grated Parmesan (if using), salt, and black pepper. Mix thoroughly with a fork until smooth and evenly combined. Taste and adjust salt or garlic to preference.

Spread butter on bread

Using a knife or offset spatula, spread a generous, even layer of the garlic butter over the cut surfaces of the bread. For sliced pieces, spread on each slice. If you prefer extra garlicky bread, press a little of the minced garlic directly onto the bread before spreading.

Optional assembly for pull-apart style

For a pull-apart loaf, after spreading butter on both cut halves, reassemble the loaf with the buttered sides facing out, wrap loosely in foil (shiny side in), and place on the baking sheet. For individual slices, leave them open-faced on the sheet.

Bake

Bake in the preheated oven for 10–12 minutes for open-faced slices, or 12–15 minutes for a wrapped pull-apart loaf, until the butter is melted and the edges of the bread begin to turn golden. If you like a crispier, more toasted top, open the foil (if used) or switch the oven to broil and broil for 1–2 minutes while watching closely so it does not burn.

Finish and serve

Remove the bread from the oven. If using Parmesan, sprinkle a little extra on top immediately so it melts slightly. Optionally sprinkle red pepper flakes or chopped basil. Let rest 1–2 minutes, then slice (if a whole loaf) and serve warm.

Finishing (optional)

If desired, sprinkle red pepper flakes or fresh basil over the hot bread just before serving for a flavor and color boost. Serve immediately.