Preheat the oven: Set your oven to 400°F (200°C).
Line a baking sheet with foil or parchment for easy cleanup.
Split the bread: Slice the loaf in half lengthwise to create two long pieces. If using a baguette, you can also cut it into smaller sections first for easier handling.
Make the garlic-herb butter: In a bowl, mix the softened butter, minced garlic, parsley, chives, thyme, crushed red pepper flakes, salt, pepper, lemon zest, and olive oil. Stir until smooth and spreadable.
Spread generously: Using a spatula or butter knife, coat the cut sides of the bread evenly.
Don’t forget the edges. If using Parmesan, sprinkle it evenly over the top.
Bake until golden: Place the bread cut-side up on the baking sheet. Bake for 10–12 minutes, until the butter is melted and the edges are lightly toasted.
Optional broil for crisp edges: Switch to broil on high for 1–2 minutes to deepen the color.
Watch closely—garlic can burn fast.
Rest and slice: Let the bread cool for 2–3 minutes so the butter sets slightly. Slice into thick pieces and serve warm.