Begin by bringing a large pot of salted water to a boil over high heat. Add 8 ounces of short pasta and cook until al dente, about 7-9 minutes. Drain the pasta and set aside, reserving about half a cup of the starchy pasta water for later.

In a medium pot, melt 2 tablespoons of unsalted butter over medium heat. Sprinkle in 2 tablespoons of all-purpose flour, whisking continuously for about 1-2 minutes until the mixture turns a light golden color.

Slowly pour in 1 cup of heavy cream while whisking vigorously. Continue cooking for about 2-3 minutes until it thickens slightly.

Remove the pot from the heat and add 1 round of Boursin cheese and 1 cup of grated white cheddar. Stir until both cheeses melt completely into a rich and creamy sauce.

Gently fold the cooked pasta into the cheese sauce, ensuring every piece is coated. If the mixture feels a bit dry, add a splash of reserved pasta water or milk.

In a small skillet, melt the remaining 2 tablespoons of unsalted butter. Add 1 cup of plain breadcrumbs and toast for about 2-4 minutes until golden brown and fragrant.

Transfer the creamy Boursin Mac and Cheese to a serving dish and sprinkle the toasted breadcrumbs on top. Serve hot and enjoy!