Cook the Pasta: Start by boiling a large pot of salted water. Add the elbow macaroni and cook until al dente, about 8-10 minutes. Drain and set aside while you prepare the cheese sauce.

Make the Cheese Sauce: In a medium saucepan, melt the butter over medium heat. Once melted, whisk in the flour until smooth. Gradually pour in the whole milk and heavy cream, stirring constantly until the mixture thickens and bubbles, about 5-7 minutes.

Add the Cheese: Lower the heat and add the shredded cheddar cheese to the sauce. Stir until the cheese has fully melted, creating a smooth and creamy consistency.

Combine Ingredients: Gently fold in the chopped brisket and cooked macaroni with the cheese sauce, ensuring every piece of pasta is coated.

Serve or Bake: You can serve it right away, or transfer the mixture to a greased baking dish and bake at 350°F for about 20 minutes, until bubbly and golden on top.