Step 1: Cook the Pasta

1. Bring a large pot of salted water to a boil.
2. Add the pasta and cook until just al dente, following the package instructions (usually 8-10 minutes).
3. Drain the pasta, reserving about 1 cup of pasta water, and set aside.

Step 2: Prepare the Alfredo Sauce

1. In a large skillet or saucepan, melt the butter over medium heat.
2. Add the minced garlic and sauté for about 1 minute until fragrant, but do not brown the garlic.
3. Pour in the heavy cream, stirring continuously until it comes to a gentle simmer.
4. Gradually add the grated Parmesan cheese, stirring until fully melted and smooth. The sauce should thicken slightly.
5. Season with salt, black pepper, and a pinch of nutmeg, if using. Simmer for another 2-3 minutes, then remove from heat.

Step 3: Assemble the Pasta Bake

1. Preheat your oven to 375°F (190°C).
2. In a large mixing bowl, combine the cooked pasta with the Alfredo sauce, making sure each piece is well coated.
3. Add in the chopped spinach, sundried tomatoes, Italian seasoning, and red pepper flakes, stirring until evenly distributed.
4. Fold in the ricotta cheese and half of the shredded mozzarella, ensuring the cheeses are mixed throughout.
5. Season with additional salt and pepper as needed.

Step 4: Layer and Top with Cheese

1. Transfer the pasta mixture into a greased 9×13-inch baking dish.
2. Sprinkle the remaining mozzarella and the grated Parmesan cheese evenly over the top.
3. Add a final crack of black pepper and a sprinkle of chopped fresh basil.

Step 5: Bake and Serve

1. Cover the baking dish with aluminum foil and bake for 20 minutes.
2. Remove the foil and bake for an additional 10-15 minutes, or until the top is golden brown and bubbly.
3. Let the pasta bake cool for a few minutes before serving.
4. Garnish with more fresh basil and extra Parmesan if desired.