Preheat oven to 400°F (200°C) and grease a 9x13 inch baking dish.
Cook penne pasta according to package directions, drain, and spread evenly in the baking dish.
In a medium saucepan, melt 1/4 cup butter over medium heat.
Add minced garlic and flour to the melted butter and sauté for 1-2 minutes until fragrant.
Gradually whisk in chicken broth and heavy cream until smooth.
Stir in Dijon mustard, brown sugar, apple cider vinegar, salt, and black pepper.
Simmer the sauce for 2-3 minutes, stirring occasionally, until it thickens slightly.
Remove from heat and stir in shredded Swiss cheese until fully melted.
Layer cooked chicken evenly over the pasta, then sprinkle chopped ham on top.
Pour the cheese sauce evenly over the chicken and ham, coating all ingredients.
Mix panko bread crumbs, melted butter, and garlic powder in a small bowl.
Sprinkle the panko mixture evenly over the casserole to create a crispy topping.
Bake uncovered for 15-20 minutes until the topping is golden and casserole is bubbly.
Remove from oven, let cool slightly, then serve warm.