Preheat oven to 350°F (175°C).
Boil elbow macaroni in salted water according to package instructions until al dente. Drain and set aside.
In a saucepan, melt butter over medium heat. Stir in flour and cook for 1-2 minutes to form a roux.
Gradually whisk in whole milk, cooking until the sauce thickens and becomes smooth.
Remove from heat and stir in shredded sharp cheddar cheese until melted and creamy.
Season the cheese sauce with salt and black pepper.
Combine cooked macaroni with cheese sauce, mixing well.
Transfer the mac and cheese to a shallow baking dish or white ceramic bowl suitable for baking.
Sprinkle breadcrumbs evenly over the top, followed by a little extra shredded cheese if desired.
Bake in the preheated oven for 20-25 minutes, or until the topping is golden brown and crispy.
Serve warm, garnished with a sprinkle of extra cheese and breadcrumbs on top.