Preheat oven to 375 degrees F. Generously coat twelve 2 1/2-inch muffin cups with cooking spray; set aside. Lightly brush one side of bread slices with melted butter. Press bread slices, buttered sides up, into the prepared muffin cups.
In a small bowl combine tuna, mayonnaise, and honey mustard. Stir in cheese, shallot, and dried cranberries. Divide tuna mixture among bread-lined muffin cups.
Bake about 15 minutes or until filling is hot and bubbly. Remove tuna cups from muffin cups; let stand for 5 minutes before serving. If desired, garnish with fresh dill.