Bring a large pot of salted water to a boil over high heat. Add macaroni pasta and cook until al dente, about 7-8 minutes. Drain and set aside.

In a medium saucepan, melt 4 tablespoons of butter over medium heat. Sprinkle in ¼ cup of flour, whisk continuously for about 2 minutes until light golden brown.

Gradually pour in 2 cups of milk, whisking to avoid lumps. Cook on medium-high for about 4-5 minutes until thickened.

Remove from heat and stir in 8 ounces of chopped Brie cheese until melted and smooth.

Fold the cooked macaroni into the cheese sauce until well combined.

Preheat your oven to 350°F (175°C). Pour the mixture into a greased 2-quart baking dish and sprinkle with breadcrumbs. Bake for 20 minutes until golden brown.

Let cool for a few minutes, then serve warm.