Prepare lasagna noodles according to the manufacturer's instructions. This typically entails boiling a pot of water, cooking for about 10 minutes, or until al dente. Drain and set aside.The pasta will cook another hour in the oven, so make sure not to overcook them during this stage!
Prepare Ingredients
Preheat the oven to 350 degrees Fahrenheit.
Lightly coat the bottom and sides of a large baking baking dish with olive oil and set aside.Mine is 13x9 inches, but any larger-sized baking dish will do. You can always cut the lasagna sheets to different sizes.
Halve the tomatoes and finely chop the spinach. I sometimes don't like to break out the big cutting board, so I'll pulse the spinach in a food processor. Although, you can easily just chop it up.
Crumble the fresh mozzarella and grate the Grana Padano cheese.Make sure to reserve about 1/2 cup of the Parmesan and mozzarella. This will go on top of the final layer.
Assemble Lasagna
Arrange noodles in the bottom of the baking dish. They should slightly overlap to keep the noodles from separating.
Top with 1/2 of the spinach, 1/2 of the ricotta, 1/2 of the tomatoes, 1/3 of the mozzarella, and 1/3 of the Grana Padano.
Repeat layering noodles and the same amount of toppings.
Top off with a final layer of noodles and the reserve amount of mozzarella and Grana Padano.
Bake for 50-60 minutes. The lasagna should be thoroughly heated throughout and the cheese on top will begin to brown. Let cool slightly and cut into 2-inch squares. Serve immediately.
Tips, Tricks, & Notes
Lasagna is best served immediately. However, if you have leftovers, lasagna will keep for 3-5 days in an airtight container in the refrigerator. Just preheat the oven to 350 degrees Fahrenheit and reheat in a baking dish for 15 minutes, or until hot.