Heat olive oil in a large skillet over medium heat. Add diced onion and sauté until translucent, about 5.
Stir in minced garlic and cook for 1.
Add ground beef, breaking it apart as it cooks. Brown for 7 to 10.
Drain excess fat, then stir in crushed tomatoes, tomato paste, dried basil, oregano, salt, and black pepper. Simmer for 15.
In a medium bowl, combine ricotta cheese, egg, and a pinch of salt. Mix until smooth.
Spread a thin layer of meat sauce in a 9x13-inch baking dish. Place 4 lasagna noodles over the sauce.
Spread half of the ricotta mixture over the noodles, then add a layer of meat sauce followed by a third of the mozzarella cheese. Repeat layers.
Finish with a final layer of noodles, remaining meat sauce, and top with remaining mozzarella and Parmesan cheese.
Cover with aluminum foil and bake in a preheated oven at 375°F for 25. Remove foil and bake for an additional 15.
Let cool for 10 to 15 before serving.