1. Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish and set aside.
2. Cook the macaroni according to package instructions until al dente. Drain and set aside.
3. In a large skillet, heat the olive oil over medium heat. Add the Italian sausage and cook until browned, about 5-7 minutes. Remove sausage from skillet and set aside.
4. Add the minced garlic to the skillet and sauté until fragrant, about 1 minute. Stir in the sun-dried tomatoes and Italian seasoning, cooking for another 2 minutes.
5. Sprinkle the flour over the tomato mixture, stirring constantly for 1 minute to cook off the raw flour taste.
6. Gradually whisk in the milk and heavy cream, bringing the mixture to a gentle simmer. Continue whisking until the sauce thickens, about 5 minutes.
7. Remove the skillet from heat and stir in the mozzarella and Parmesan cheeses until melted and smooth. Season with salt and pepper to taste.
8. Combine the cooked macaroni, sausage, and cheese sauce in a large bowl, mixing until everything is well coated.
9. Transfer the mixture to the prepared baking dish, spreading evenly. Sprinkle with additional mozzarella cheese, if desired.
10. Bake in the preheated oven for 20-25 minutes, or until the cheese is bubbly and golden brown.
11. Remove from the oven and let it cool for a few minutes before garnishing with fresh basil and serving.

As you prepare this dish, remember that cooking is an act of love. Let each step be a moment of joy, much like the times I spent with my abuela in her kitchen.