Add the eggs, half and half, mustard, nutmeg, and salt & pepper to a large bowl. Whisk together until the mixture's completely smooth.
4 large eggs, 1 1/2 cups half & half, 1 1/2 tsp Dijon mustard, pinch nutmeg, salt & pepper
Add the bread, stirring until all of the bread is well coated with egg.
6 cups slightly stale, cubed French bread
Stir in the ham and half of the cheese until evenly incorporated.
2 cups diced ham, 1 1/2 cups shredded Swiss cheese
Lightly spray an 8x8" baking dish with non stick cooking spray. Pour the egg mixture out into the pan, evenly spreading it out. Sprinkle the remaining cheese evenly out over the dish.
Bake at 350 degrees for 40 minutes, or until golden brown on top and a butter knife inserted in the center comes out clean.
Let the casserole rest 2 minutes before slicing and plating. If using, sprinkle each slice lightly with sifted powdered sugar. Drizzle with the warm raspberry preserves, and serve immediately.
powdered sugar, warmed raspberry preserves