Step 1: Prepare the Marinara Sauce

Start by preparing the marinara sauce. In a large saucepan, heat 2 tablespoons of olive oil over medium heat. Add the chopped onion and sauté for 3-4 minutes until soft and translucent. Add the minced garlic and cook for another 1-2 minutes until fragrant. Pour in the crushed tomatoes, and add the dried basil, oregano, salt, and pepper. Stir to combine.

Bring the sauce to a simmer, reduce the heat to low, and let it cook for about 20-25 minutes, stirring occasionally. The sauce should thicken slightly and develop a deep, rich flavor. Once it’s done, remove it from the heat and set it aside.

Step 2: Cook the Manicotti

While the marinara sauce is simmering, bring a large pot of salted water to a boil. Add the manicotti tubes and cook according to the package instructions, usually for about 8-10 minutes, until they are just al dente. Be careful not to overcook the pasta since it will bake in the oven later. Drain the manicotti and lay them out on a baking sheet to prevent them from sticking together.

Step 3: Prepare the Spinach and Ricotta Filling

Now it’s time to prepare the filling. If you’re using frozen spinach, make sure it’s thoroughly thawed and drained—you don’t want any excess moisture in the filling. You can press the spinach in a fine-mesh sieve or wrap it in a clean kitchen towel and squeeze out the moisture.

In a large bowl, combine the ricotta cheese, mozzarella cheese, Parmesan cheese, and the beaten egg. Add the drained spinach, garlic powder, dried oregano, salt, and pepper, and mix everything together until it’s well incorporated. The filling should be thick and creamy.

Step 4: Stuff the Manicotti

Carefully stuff each manicotti tube with the spinach and ricotta filling. You can use a spoon or a piping bag to fill the tubes, but be gentle to avoid breaking them. If you’re using a spoon, it helps to hold the manicotti vertically while you fill each one.

Step 5: Assemble the Dish

Preheat your oven to 375°F (190°C). Spread a small amount of the marinara sauce on the bottom of a large baking dish (about 9×13 inches) to prevent the manicotti from sticking. Then, arrange the stuffed manicotti tubes in the dish, being careful not to overcrowd them.

Once all the manicotti are arranged, pour the remaining marinara sauce over the top, ensuring that the pasta is well covered. Sprinkle the shredded mozzarella cheese on top of the sauce. Cover the dish with aluminum foil and bake for 30 minutes.

Step 6: Bake and Finish

After 30 minutes, remove the foil and continue baking for an additional 15-20 minutes until the cheese is bubbly and golden brown. If you want the top to be extra crispy, you can broil it for the last 2-3 minutes, but keep an eye on it so it doesn’t burn.

Step 7: Garnish and Serve

Once the manicotti is finished baking, remove the dish from the oven and let it cool for about 5 minutes. Garnish with fresh basil leaves for a burst of color and added flavor, then serve the manicotti with a side salad and garlic bread for a complete meal. Enjoy the rich, comforting flavors of this classic Italian dish!