Melt butter in a small saucepan over low heat. Add garlic to pan; cook 15 minutes, stirring occasionally. Arrange baguette slices in a single layer on a baking sheet. Broil bread 5 inches from heat 1 minute or until lightly browned. Turn slices over; brush with melted butter. Discard garlic. Top each bread slice with 1 1/2 teaspoons grated Parmigiano-Reggiano cheese. Broil 2 minutes or until cheese is melted and golden brown.