In a large bowl, stir together marinara sauce, oregano, and garlic. Pour about a third of the sauce mixture evenly into a 7- by 11-inch microwave-safe baking dish. Stir water into remaining sauce; set aside. In a food processor, combine the washed spinach and basil. Process until everything is finely chopped. Add in the ricotta cheese and 1 egg, and process again until the cheese, egg, spinach, and basil are all fully mixed.
Rinse uncooked lasagna noodles with cold water. Then arrange a third of the uncooked noodles in a single layer atop sauce in baking dish. Spread a thin layer of the spinach/cheese mixture atop the uncooked noodles, and then add a layer of cheddar cheese and mozzarella cheese (about a third of each cheese). Next, pour a third of the remaining sauce to make the next layer. Add another layer of lasagna noodles on top, and repeat with another layer of spinach/ricotta cheese, followed by cheddar and mozzarella. Finally, repeat with one more layer of sauce, lasagna, ricotta/spinach, and cheddar/mozzarella. Cover and microwave on medium heat (50%) for 20 minutes, giving dish a half-turn after 10 minutes. Remove from the microwave at this point and let the lasagna stand, covered, for about 5 minutes. Return to the microwave, and cook on high for 15 minutes, again, turning the dish at 10 minutes.
Remove from the microwave, and let it stand with a cover over it for 10 to 15 minutes. Cut into squares, serve and enjoy!