Cook the Pasta: Bring a large pot of salted water to a boil. Add the elbow macaroni and cook until al dente according to package instructions. Drain and set aside.​

Prepare the Cheese Sauce: In a medium saucepan over medium heat, melt the butter. Once melted, whisk in the flour and cook for about 1-2 minutes until the mixture is golden and bubbly, forming a roux.​

Add Milk: Gradually whisk in the whole milk, ensuring no lumps form. Continue to cook, stirring constantly, until the mixture thickens, approximately 5 minutes.​

Incorporate Cheeses: Remove the saucepan from heat and stir in the shredded cheddar and Gruyère cheeses until fully melted and the sauce is smooth. Season with salt, black pepper, and paprika.​

Combine Pasta and Sauce: Add the cooked macaroni to the cheese sauce, stirring until the pasta is evenly coated.​

Bake (Optional): Preheat the oven to 350°F (175°C). Transfer the macaroni and cheese mixture to a greased baking dish. If desired, sprinkle breadcrumbs evenly over the top for a crunchy topping. Bake for 20-25 minutes until the top is golden brown and the sauce is bubbling.​

Garnish and Serve: Remove from the oven and let it cool slightly. Garnish with freshly chopped parsley before serving.