Preheat oven to 375 F degrees.
In a sauce pan or skillet, cook the ground meat until no longer pink. Add chopped onion, 1 tbsp of the oregano, salt, pepper and continue cooking until onion is cooked through and translucent.
Add the marinara sauce to the skillet and the cup of water. Stir and bring to a boil. Remove from heat and set aside.
In a small bowl combine the ricotta cheese, 1 tbsp oregano, eggs, Parmesan cheese, salt and pepper. Mix well.
In a baking dish that's about 9x13 inches, start assembling your lasagna. I usually start with a couple ladles of the sauce at the bottom, this is especially necessary now that the noodles aren't cooked. Lay 3 lasagna noodles over the meat sauce. Next layer with ricotta mixture and about 1/2 cup of the mozzarella cheese. Add another 3 lasagna noodles, meat mixture, ricotta mixture, mozzarella. Repeat until you have 4 layers of noodles, and end with ricotta cheese and mozzarella cheese.
Bake in the oven for about an hour. It will take the entire hour for the noodles to cook. You may try with a fork to ensure noodles are cooked.