Preheat the oven to 350℉. Spray a 9x13-inch casserole dish with cooking spray. Set aside.
Bring a large pot of salted water to a boil. Cook the lasagna noodles according to package instructions, drain and set aside. About 10 minutes.
While the noodles are cooking, prepare the meat sauce. Heat the olive oil in a skillet over medium/high heat. When the oil becomes fragrant add the Italian sausage and onions. Cook for 5-6 minutes, until there is no pink left in the sausage. Add the garlic and cook for an additional minute. Add the marinara sauce and set aside.
Add the cottage cheese, parmesan cheese, salt, pepper, and eggs to a bowl and mix them together. Set aside.
To assemble the lasagna spread 1 cup of the marinara sauce on the bottom of the casserole dish. Layer 4 noodles on top of the sauce, and cover the bottom. Spread half of the cottage cheese mixture on top of the noodles. Sprinkle ½ cup of the mozzarella cheese on top of the cottage cheese. Spread ¾ cup of the marinara sauce on top of the mozzarella. Repeat the steps until you get to the top layer of noodles.
Spread the remaining sauce over the noodles. Sprinkle the remaining 1 cup of mozzarella on top of the sauce. Cover the casserole dish with tin foil and bake for 25 minutes. Remove the tin foil and bake for an additional 10 minutes.
Allow the lasagna to rest for 10 minutes before serving.