In a medium pan, heat the oil. Add the minced garlic and sauté for a minute. Now add the chopped onion and fry until light brown.

Add the chopped spinach and let it cook for few minutes. Make sure that you cook the spinach down until all the water has evaporated. Add salt and pepper to taste.

Transfer the mixture to a large bowl and let it cool down. Once it comes to room temperature add the nutmeg, ricotta cheese and the parmesan cheese. Mix well and keep aside.

Heat a large pot of water and add the lasagna sheets to it. Follow the manufacturer’s direction and cook the lasagna until ¾th done. The sheets should be cooked but still have a bite to them. Do them cook them entirely since, they would also cook in the oven.

Remove the sheets and run them under cold water. Layer the sheets in a kitchen towel until ready to use.

Preheat the oven to 350 F.

Spray a 9 x 13 baking dish with cooking spray. Layer the bottom with about ½ cup of marinara sauce.

Now lay 4 pasta sheets over the tomato sauce, slightly overlapping one another.

With a spatula, spread half of the spinach ricotta mixture over the pasta.

Now add ⅓rd of the tomato sauce and spread it all around.

Now again layer with 4 pasta sheets and repeat the spinach layer and the sauce layer.

Finally add the last 4 pasta sheets and then add the remaining tomato sauce.

Spread the mozzarella cheese evenly on the top and bake it covered for about 30 mins.

Then open the cover and cook it for 15 more minutes until it is bubbling at the edges and the cheese is all melted. Place it under broiler for few seconds to brown the top layer.

Remove it from the oven and let it set for about 15 to 20 minutes, before slicing it.