You want a squishy-soft french loaf--it crisps up well on the grill and stays fluffy inside.
Melt butter with garlic over low heat.
Slice loaf in half lengthwise and toast, crust side down, on a grill until crunchy, about 3 minutes. Turn and toast cut side about 3 minutes.
Brush garlic butter onto bread and cut into 1-in. slices.