Rub entire breast with butter and season with salt and pepper.
Place in a small roasting pan and roast for 15 minutes.
Reduce the heat to 350 degrees and continue roasting until a thermometer inserted into the center registers 155 degrees, about 1 – 1 ½ hours.
Remove from the oven, loosely tent with foil and let rest 10 minutes before slicing.
Put the milk in a small saucepan and bring to a simmer over low heat.
Melt the butter over medium-high heat in a medium saucepan.
Whisk in the flour and cook for 1 minute. Whisk in the hot milk, bring to a boil and cook, whisking constantly, until thickened and the flour has cooked out, about 4 to 5 minutes.
Remove from the heat and whisk in the cheeses and cook until the cheddar has melted; season with nutmeg and salt and pepper to taste.
Whisk together the eggs, milk, salt, and pepper in a medium baking dish. Dip each slice of bread in the mixture and let sit about 10 per side seconds, or until completely soaked through.
Heat 1 tablespoon of butter and 1 tablespoon of oil in a large nonstick sauté pan over medium-high heat. Cook 2 slices of the bread at a time until golden brown on both sides. Repeat with the remaining bread.
Preheat the broiler.
Place 4 slices of the egg bread on a baking sheet, place under the broiler and heat on both sides for 20 seconds just to warm through. Repeat with the remaining bread.
Top each slice of bread with 2-3 slices of turkey and 2 slices of tomato, ladle sauce over the top and divide the cheddar cheese and parmesan over the top of each slice. Place under the broiler and cook until bubbly and the top is golden brown. Remove from the oven, top each slice with 2 slices of bacon and sprinkle each slice with chives and parsley.