Mac and cheese:

• Preheat the oven to 350°F/180°C. Butter the casserole dish (no need to butter a cast-iron pan).
• Cook macaroni: Bring a large pot of water to a boil. Add salt generously and cook ½ lb pasta (250 g) according to package instructions.
• In the meanwhile, make the cheese sauce.
• Roux: Melt 2 ½ tablespoons of butter in a large skillet. Sprinkle 2 ½ tablespoons of flour on top and whisk until the flour is lightly golden, 1-2 minutes. Slowly pour 2 ½ cups milk (600 ml) into the mixture while constantly whisking to break up the clumps. Whisk on medium heat until the sauce starts to simmer and thickens slightly.
• Add cheese: On the lowest heat possible, add ½ cup cream cheese (110 g), 2 cups of grated cheese (200 g), a few gratings of nutmeg, salt, and pepper. Stir well until smooth. Adjust the taste with salt and pepper.
• Combine: Drain macaroni. Add them to the pan and stir to combine. Transfer to the prepared baking dish.
• Topping:
• Combine topping ingredients: Melt 1 tablespoon of butter in a small pan. Add the ¾ cup breadcrumbs (45 g) and ¼ cup grated cheese (30 g). Stir to combine. Cover mac and cheese with the mixture.
• Bake for 20-25 minutes until bubbling and golden brown.