Preheat oven to 375°F (190°C). Cook pasta until al dente, drain and set aside. Grease a 9x13 inch baking dish.

In large skillet over medium heat, cook diced bacon until crispy. Remove with slotted spoon, reserve 2 tablespoons bacon fat.

Add ground beef to skillet with bacon fat. Cook until browned, add onion and cook until softened, about 5 minutes. Add garlic, cook 1 minute.

Stir in Worcestershire sauce, garlic powder, onion powder, salt, and pepper. Remove from heat and set aside.

In large saucepan, melt butter over medium heat. Whisk in flour and cook 1-2 minutes, whisking constantly to form roux.

Slowly pour in milk while whisking continuously. Cook, whisking frequently, until thickened, about 5-7 minutes.

Remove from heat, stir in cream cheese until smooth. Add cheddar, American, and mozzarella, stirring until melted.

In baking dish, combine pasta, beef mixture, most bacon, and cheese sauce. Stir gently to combine evenly.

Mix panko breadcrumbs, remaining cheddar, and melted butter. Sprinkle evenly over mac and cheese.

Bake 25-30 minutes until bubbly around edges and golden brown on top. Cover with foil if browning too quickly.

Let cool 5-10 minutes to set slightly. Garnish with reserved bacon bits and fresh chives.

Serve immediately while hot and creamy. Enjoy this ultimate comfort food creation!