1. Preheat the oven to 375°F (190°C)

2. Cook the lasagna noodles according to package instructions

3. In a skillet, brown ground beef with onions and garlic until cooked through

4. Add marinara sauce and simmer for 10 minutes

5. In a baking dish, layer the noodles, meat sauce, ricotta cheese, and mozzarella cheese

6. Repeat the layers until all ingredients are used up, ending with a layer of cheese on top

7. Cover with foil and bake for 30 minutes

8. Remove foil and bake for an additional 15 minutes until cheese is bubbly and golden brown