Gather all ingredients. Preheat the oven to 400 degrees F (200 degrees C). Spray 2 mini muffin pans with cooking spray.
Bring a large pot of lightly salted water to a boil. Cook elbow macaroni in the boiling water, stirring occasionally, until tender yet firm to the bite, about 8 minutes; drain.
Melt butter in a large soup pot over medium heat. Whisk in flour until smooth. Add milk and bring to a simmer. Add 1 1/2 cups Cheddar cheese, cream cheese, salt, and pepper. Stir until smooth. Turn heat off.
Add drained pasta and beaten egg to cheese sauce and stir until evenly combined.
Using a small spoon, divide mixture between mini muffin tins. Sprinkle each mac and cheese bite with remaining Cheddar cheese.
Bake in the preheated oven until golden brown, about 16 minutes. Remove from oven and let stand 5 minutes before serving.
