Set a large pot of water to boil on high heat. When water has come to a boil, salt the water generously and add the lasagna noodles. Cook to al dente according to the package directions.
Microwave or steam frozen spinach until defrosted and drain excess liquid using a tea towel. Remove as much liquid as possible.
Beat egg in a large bowl until light & frothy.
Add spinach, ricotta, Parmigiana, all but 1 cup of mozzarella, and salt and pepper to the bowl with the beaten egg. Mix well until all ingredients are completely combined.
When lasagna noodles are cooked, drain the water and rinse the noodles under cold water. Place the noodles on a tea towel to dry.
Tomato Sauce
Crush garlic cloves but do not break them up.
Pour 28 g (2 tbsp) of extra virgin olive oil into a large pot and add the garlic. Turn the heat to low and cook for a few minutes just until the garlic becomes fragrant and is starting to brown. Make sure not to let the garlic brown. Remove the garlic from the pot.
Add tomato sauce to the pot and cook over medium-high heat for about 20 minutes.
Remove from the heat and add the chopped basil and stir.
Assembly
Preheat oven to 227 Celsius (350F).
Add 1 cup of tomato sauce to a large baking dish making sure the bottom is covered.
Add 1/4 cup of the ricotta spinach mixture to the end of each lasagna noodle and roll up.
Place each roll-up seam side down in the baking pan with the tomato sauce in one level.
Top with the remaining tomato sauce and the mozzarella cheese.
Cover the baking pan with foil and bake on the middle rack for 35 minutes. Remove the foil and continue baking for another 10 minutes or until the mozzarella is melted and turning brown.
Allow to sit for 5-10 minutes before serving.
Notes
See the "How To Make This" & "Tips For Success" sections above the recipe for more detailed information on the process.