Preheat oven to broil. If making honey mustard from scratch (see recipe notes), whisk ingredients until smooth and combined. Spread a layer of honey mustard onto bread.
Grate smoked cheddar cheese, slice apples and avocados. Add slices of turkey and grated cheese to bread.
Transfer sandwich to a baking sheet and broil for 3-4 minutes or until the cheese is melted, browned and bubbly. Add avocado, apple slices and greens.
Close and cut sandwich, and enjoy!