This sandwich does not store well, and should be eaten right when it comes out of the oven.
I have made a version of this sandwich with a thin layer of cranberry sauce on top of the bread, under the roasted turkey breast and mornay…really came out tasting incredible, where the balance of the sweet cranberry sauce contrasted wonderfully with the rich flavors of everything else. But it is unfortunately not included in this more classic Kentucky Hot Brown recipe. If that cranberry sauce idea sounds decent to you, try it out!