1/4 cup unsalted butter or margarine, melted
24 soft white sandwich bread slices
Preheat oven to 400 degrees F.
Using a pastry brush, coat inside of 24 miniature (2-inch diameter) muffin cups with melted butter or margarine. Set aside.
Using a 2 1/2-inch round cutter, cut a round from each slice of bread. Save scraps from bread to dry for bread crumbs. Push each round gently into buttered muffin cups, pressing snugly against bottom and sides. If bread tears, patch with a small piece of bread from scraps; pat patches in firmly. Bake shells in preheated oven until lightly browned — about 10 minutes. Remove from muffin pans; cool on wire racks.
When completely cooled, shells may be packed in plastic freezer bags and frozen up to 3 months. Or fill for immediate use.