Heat oven to 450º F. Slice the rolls in half horizontally.Hollow them out by removing most of the soft crumb from the tops and bottoms. Distribute the mozzarella evenly inside each of the 4 hollowed-out halves. Place 1/3 cup of the ricotta into each bottom
half. Top each bottom half with 3 basil leaves. Put the 2 halves of the rolls back together and wrap each sandwich in foil. Bake until the outsides are crispy and the cheeses are melted, 25 minutes. Let cool 5 minutes. Slice in half and serve.