Pass the warmed loaf around the table and let guests tear off their own pieces. Leftover garlic-herb butter tastes delicious on top of grilled steak, chicken, or fish.
Preheat oven to 350 degrees. Using a mortar and pestle, crush together garlic and salt to form a paste. Transfer to a medium bowl. Add parsley, chives, lemon juice, and butter; stir with a wooden spoon until well combined.
Place bread on a baking sheet. Warm bread in oven until crust is crisp, about 10 minutes. Serve with the butter.
Butter can be refrigerated in an airtight container up to 2 weeks.