preheat oven to 400°F and arrange the oven racks in the upper and bottom thirds. Grease one 12 count muffin tin with butter or spray.

cook pasta according to package directions. set aside until needed.

in a saucepan over medium heat, combine butter and flour. whisk until butter is melted and mixture is smooth, about 1 minute. while whisking, slowly add milk and bring to a simmer. add 1.5 cups of cheese, the cream cheese, salt and pepper. stir and cook until smooth and creamy. remove from heat.

in a large bowl, stir to combine pasta, cheese sauce and egg. spoon mac and cheese into muffin tin and top with the remaining cheese. cook for 15 minutes starting on the bottom rack, switching the position of the tin to the top rack midway through baking. remove from oven, let cool for 5 minutes, then serve.