Bring water to a boil and cook macaroni pasta. While it is cooking, prepare pasta bake.
Preheat oven to 350°F. Prepare 6 Cup Bundt pan with baking spray. Add 1/2 cup shredded cheddar cheese to the bottom of the Bundt pan. In a large bowl, mix melted butter, 2 Tablespoons bread crumbs, cayenne pepper, mustard and paprika together. Whisk in the buttermilk, half & half and eggs until incorporated. Add in the remaining cheeses. Fold in the hot cooked macaroni and stir to incorporate. Pour into prepared Bundt pan.
Bake in preheated oven for 25 minutes. Remove pan from oven and sprinkle with the last 2 Tablespoons of bread crumbs. Bake 5 -8 more minutes or until breadcrumbs are browned. Cool for 20-30 minutes.
When ready to unmold, gently loosen pasta bake from the pan on all sides with silicone spatula or a flexible tool that won’t scratch. Shake pan to loosen further and invert Bundt onto a platter. Serve immediately.
