Baked Shells

Preparation

1. Step 1

   Preheat the oven to 400°F.

   Step 2

   Bring a large pot of water to a boil for the pasta. Salt the water and cook the shells for 2 to 3 minutes less than the package directions. Heads up: You will need to reserve 1/2 cup starchy cooking water just before draining the pasta.

   Step 3

   Meanwhile, heat a medium-size pot or high-sided skillet over medium heat with the EVOO. Add the onions and garlic and sauté for 3 to 4 minutes. Add the spinach, pulling it apart as you add it, and season with a little freshly grated nutmeg, salt, and pepper. When the spinach mixture is warm through, transfer it to a small dish and reserve. Return the pot to the heat, add the butter, and melt. Add the tomatoes and break up with a spoon. Season with salt and pepper, add the basil leaves, and cook to thicken the sauce, 7 to 8 minutes.

   Step 4

   Drain the pasta and return the pasta to the hot pot. To the pasta, add the spinach, reserved starchy water, ricotta cheese, and half of the Parmigiano-Reggiano. Adjust the salt and pepper and transfer to a baking dish. Top the pasta mixture with the tomato sauce, mozzarella, and remaining Parmigiano. Bake until the cheeses are melted and bubbly, 6 to 8 minutes.