Preheat oven to 375 degrees F (190 degrees C). Line a 9x13-inch baking dish with parchment paper.
Bring a large pot of water to a boil. Cook elbow macaroni in the boiling water, stirring occasionally until almost cooked through and firm to the bite, about 7 minutes. Drain and transfer to a large bowl. Sprinkle macaroni with 1/2 teaspoon salt and stir 1/2 cup butter into the pasta.
Mix 1/4 cup butter, sour cream, cream cheese, sharp Cheddar cheese, and egg yolk together in a bowl. Stir flour, 1/2 teaspoon salt, cayenne pepper, and milk into the sour cream mixture.
Spread 1/4 cup sour cream sauce over bottom of prepared baking dish. Stir remaining sour cream sauce into macaroni. Pour macaroni into baking dish atop sauce layer; sprinkle mild Cheddar cheese over the casserole.
Bake in the preheated oven until heated through and cheese topping has melted, about 15 minutes.
Hello Everyone, I'm back with another monthly recipe for you all. Last month I had some friends over for dinner and need a side to go with the rest of the food. So Hubby and me decide mac n cheese would be a great side. So I hop on Allrecipe.com and got this one. The mac n cheese was super good. Also if you are a mac n cheese lover. Go and check out my Walter's chicken mac.
HAVE A GREAT TUESDAY.