Preheat oven to 250°F.
Peel garlic cloves and place them in an oven-safe dish.
Pour in enough olive oil to fully submerge the garlic.
Add a pinch of salt and optional herbs (like thyme or rosemary).
Bake for 2 hours, until garlic is soft, golden, and spreadable.
In a bowl, mash the softened garlic confit cloves.
Add butter and mix until smooth.
Season with a little salt to taste.
Slice the French bread in half lengthwise.
Spread a generous layer of garlic butter over each half.
Top with plenty of mozzarella cheese.
Bake at 375°F for 8–12 minutes, until cheese is melted and bubbly.
Broil for 1–2 minutes for a golden, crispy top (optional).
Sprinkle with parsley and slice. Serve warm.