Preheat the oven to 375 degrees . Broil the bacon on a rack set on a baking sheet. Bake until crisp, 15 to 20 minutes.
Meanwhile, mix together the maple syrup and applesauce. Season the tomato slices with salt and pepper.
Assemble 4 sammies with bread, cheese, turkey, spinach, bacon, tomato, more cheese and bread; press slightly.
In a shallow dish, beat the eggs with the milk. In a large skillet, melt the butter over medium-low heat. Coat each sammie with the egg mixture, then add to the skillet and cook, turning once, until deeply golden, about 7 minutes. Cut the sammies and serve with the applesauce.