Begin by bringing a large pot of salted water to a rolling boil. Add uncooked macaroni elbow pasta and cook according to package directions until al dente, usually about 7 minutes. Once done, drain and rinse the pasta under cold water to stop the cooking process.

In a medium saucepan, gently simmer heavy cream over low heat until it's warm but not boiling. Stir in Gruyere, Gorgonzola, and Parmesan cheeses along with pumpkin puree. Continue stirring until the cheese is melted and the sauce is smooth and creamy.

In a separate skillet, heat olive oil over medium heat. Add the cut apples and sauté for about 4-5 minutes or until they are soft and slightly caramelized. Sprinkle with salt, pepper, cinnamon, and nutmeg as they cook.

Carefully mix the sautéed apples into the creamy cheese sauce along with the cooked pasta, stirring gently to combine all ingredients.

Preheat your oven to 350°F (175°C). Transfer the combined mixture into a greased baking dish. Spread evenly, then top it with breadcrumbs and additional cheddar cheese for a delicious crunch. Bake for 15-20 minutes, until the top is golden brown and bubbling.

Once baked, let it cool for a few minutes before serving. Serve warm with a sprinkle of fresh chopped herbs if desired.