Bring a large pot of salted water to a boil. Cook pasta until al dente. Drain, lightly oil and set aside.
In a medium sauce pan cook the sausage until no longer pink. Add onion and garlic and continue cooking for another 4 minutes.
Add marinara sauce to the sausage mixture and set aside.
In a medium bowl, blend cottage or ricotta cheese, egg, ¼ cup of the cheese blend and the chopped spinach; set aside.
Coat a 9x13” baking dish with olive oil and spread 1 cup of the sauce mixture on the bottom.
Top with 3 lasagna noodles. Spread ¼ of the cottage or ricotta cheese mixture on the noodles and layer on 1 cup of the sauce mixture. Sprinkle ½ cup cheese blend. Repeat this process three more times starting with the noodles and finish with the remaining ¼ cup of cheese blend. Sprinkle with oregano on top.
Bake uncovered at 350 degrees F for 45 minutes until hot and bubbly. Let stand 10 minutes before cutting.