Spinach and Ricotta Stuffed Shells

Prepare the Pasta

1. Bring a large pot of salted water to a boil.
2. Cook the jumbo shells according to package instructions until just al dente (usually 2 to 3 minutes less than regular cooking time so they hold their shape).
3. Drain carefully, rinse under cold water to stop the cooking process, and spread them out on a clean tray or baking sheet so they do not stick together.

Make the Tomato Sauce Base

1. Preheat your oven to 190°C (375°F).
2. In a saucepan over medium heat, warm 1 tablespoon of olive oil. Add half of the minced garlic and sauté for 1 minute until fragrant.
3. Pour in the passata or crushed tomatoes, dried oregano, 1/2 teaspoon of salt, and a pinch of black pepper. Simmer gently for 10 minutes.
4. Spread about three-quarters of the tomato sauce evenly across the bottom of a large baking dish (around 23x33 cm / 9x13 inch).

Mix the Filling

1. If using fresh spinach, sauté it in the remaining 1 tablespoon of olive oil with the remaining minced garlic until completely wilted. If using frozen spinach, ensure it is thoroughly thawed and all excess water is squeezed out with a clean kitchen towel.
2. Finely chop the spinach.
3. In a large mixing bowl, combine the chopped spinach, ricotta, egg, ground nutmeg, half of the grated Parmesan, 1/2 teaspoon of salt, and 1/4 teaspoon of black pepper. Mix until smooth and well blended.

Assemble and Bake

1. Spoon the ricotta-spinach mixture generously into each cooked pasta shell using a spoon or a piping bag.
2. Arrange the filled shells snugly in the prepared baking dish on top of the tomato sauce layer.
3. Spoon the remaining tomato sauce lightly over the tops of the shells.
4. Scatter the shredded mozzarella and the remaining Parmesan evenly over the entire dish.
5. Cover the baking dish loosely with aluminum foil and bake for 20 minutes.
6. Remove the foil and bake for an additional 10 to 15 minutes, or until the cheese is melted, bubbly, and lightly golden at the edges.
7. Let rest for 5 to 10 minutes, garnish with fresh basil if desired, and serve warm.