Brown ground beef with onion and salt and pepper in a large skillet until meat is cooked through; drain fat from meat. Add spaghetti sauce and crushed red pepper then stir to combine. Reduce heat to low, cover and simmer meat sauce for 30 minutes.
### Make cheese mixture
Combine cottage or ricotta cheese, 1/2 cup parmesan cheese, egg, parsley, oregano, garlic and salt; stir to combine then set aside.
### Prepare mozzarella
Divide cheese in half. Shred one half and slice the other half into thin slices. I like to slice my mozzarella into thin slices using a wire cheese slicer (you can see the slices on top of the lasagna in the photo). If you don’t have something to easily cut thin slices with, just shred all of your mozzarella. You will use 1/4 of the cheese in the first layer, 1/4 in the second layer and then use the remaining half on top.
### Cook pasta
Cook lasagna noodles in liberally salted water per manufacturer’s instructions for al dente preparation.
### Assemble and cook lasagna
Drizzle the bottom of a large rectangular baking pan with olive oil. Arrange 3-4 noodles (depending how big your pan is – mine fits 3 noodles per layer) in a single layer in baking pan. Spread 1/3 of the cheese mixture over noodles. Top cheese mixture with 1/3 meat sauce. Top meat sauce with 1/4 of the mozzarella cheese. Repeat these layers two times, adding remaining mozzarella and remaining 1/4 cup parmesan cheese to the top.
Cover dish with aluminum foil then bake at 350 degrees for 35-40 minutes or until bubbly. Remove aluminum foil from dish and continue baking for 15-20 minutes or until cheese is nicely browned. Remove from oven and let stand 15-20 minutes before serving. Garnish with fresh chopped parsley if desired.