Preheat the Oven
Preheat your oven to 375°F (190°C). Grease a 9x13-inch baking dish and set aside.
Make the Cream Sauce
In a medium saucepan, combine the cream of chicken soup, sour cream, garlic powder, onion powder, salt, and pepper. Heat over medium heat, stirring until smooth and warmed through. Remove from heat.
Layer the Casserole
Spread half of the shredded chicken evenly in the prepared baking dish.
Top with half of the diced ham and 4 slices of Swiss cheese.
Pour half of the cream sauce over the layer.
Repeat the layers with the remaining chicken, ham, cheese, and cream sauce.
Add Breadcrumb Topping
In a mixing bowl, combine breadcrumbs and melted butter. Stir until evenly coated. Sprinkle the breadcrumb mixture over the top of the casserole.
Bake
Bake in the preheated oven for 25–30 minutes or until the top is golden brown and the casserole is bubbling.
Serve