In a small bowl, whisk together the mustard, mayo, maple syrup and a pinch of cayenne pepper until smooth. Set aside.

In a large shallow bowl, whisk together the eggs, milk and a pinch of salt and black pepper. Set aside.

Assemble your 4 sandwiches by layering on the maple mustard sauce, turkey breast, cheese, and arugula on 4 slices of challah bread. Finish off each sandwich with the 4 remaining slices of challah bread.

Preheat a griddle pan over medium heat and add the butter. Dip each sandwich into the egg mixture, making sure to coat each sides and place on the hot griddle pan. Cook for 3-4 minutes on each side or until brown. Work in two batches if needed.

Remove from heat and serve with a drizzle of more maple mustard sauce and garnished with fresh parsley.

Enjoy!