Place potatoes in a medium pot. Cut larger potatoes in half. Leave smaller baby potatoes whole. Cover potatoes with water and top with a lid. Place over high heat. When the water boils, salt water and cook potatoes with the lid off pot for 10 to 11 minutes, until tender.
Place a second low pot on the stove top over medium-high heat. Add apple sauce and canned cranberry sauce. Stir to combine and gently heat through, about 10 minutes.
Toast 2 slices whole grain bread and butter heavily, 1/2 tablespoon per slice. Chop into small cubes and reserve.
Add extra-virgin olive oil and sausage meat to hot skillet. Brown and crumble the sausage with a wooden spoon or heat safe spatula. Add onions and celery to the skillet then season with poultry seasoning and salt and pepper and cook 5 minutes. Add bread to the skillet and stir to combine. Dampen the stuffing with chicken stock and turn to combine. Turn off heat and cover pan loosely with foil to hold heat.
Preheat a second skillet over medium heat to prepare turkey and gravy.
Drain cooked potatoes and return to hot pot. Smash with sour cream, butter and crisped, chopped bacon. Season the smashed potatoes with salt and pepper. If they are too thick, thin them out with milk or a splash of broth.
Add 2 tablespoons butter to preheated skillet and melt it. Whisk in flour and cook 1 minute. Whisk in 2 cups stock or broth. Add the poultry seasoning, a pinch of salt and a few grinds of black pepper to the gravy. Allow it to thicken slightly.
Cut roasted turkey meat away from the breast bones of rotisserie turkey breast. If you are using deli turkey, remove from packaging and separate slices. Set turkey into gravy.
Place a bread slice on dinner plate. Use a large ice cream scoop to place a mound of stuffing on the bread. Place turkey on top of stuffing. Serve smashed potatoes and cranberries on the side. Spoon the extra gravy over potatoes and turkey sandwiches. Sprinkle the plates with chopped parsley or chives and serve.