If you’re using fresh mozzarella, slice it and set it on paper towels to absorb excess moisture. If using shredded mozzarella, skip this step.

Thaw your spinach completely and squeeze out all excess liquid. For quick thawing, immerse it in boiling water for 1 minute. Drain and then press it dry.

In a large bowl, combine the thawed spinach, ricotta cheese, and three-quarters of the grated Parmesan. Season with salt and black pepper to taste. Blend thoroughly.

Preheat your oven to 200°C (about 400°F). If using dry lasagna sheets, cook them according to package instructions until al dente.

Spread 120 ml (½ cup) of marinara sauce at the bottom of a large baking dish. Arrange a layer of lasagna sheets over the sauce.

Top with another 120 ml (½ cup) of marinara sauce, a quarter of the spinach mixture, and about one-fifth of the mozzarella. Spread this filling evenly.

Continue layering lasagna sheets, marinara sauce, spinach filling, and mozzarella. Repeat this process three more times for a total of four layers.

Place the last sheets of lasagna on top, pour the remaining marinara sauce over it, and add all the remaining mozzarella and Parmesan cheese on top.

Carefully transfer the baking dish to the oven. Bake for 25-30 minutes until the cheese is melted and the edges are golden and crisp.

Once baked, allow the lasagna to cool for 10 minutes before slicing. Garnish with fresh basil leaves if desired. Serve warm and enjoy!