Heat oven to 350º F or a grill to medium-high. Slice 1 loaf of Italian ciabatta or peasant bread in half horizontally.
Brush the halves with olive oil. Sprinkle on 1/2 cup grated Parmesan and salt to taste. Arrange the bread with the cheese facing up on a piece of foil.
Place in oven or on a grill and heat until the cheese melts, about 10 minutes.