Heat the oil in a cast-iron skillet over high heat.
3. Step
Cook the beef, salt, and pepper until the moisture has evaporated and the beef is starting to brown.
4. Step
Add the garlic and onion and cook until onions are starting to become translucent.
5. Step
Add one cup (260 g) of the marinara sauce and cook until the sauce has reduced to a paste.
6. Step
Using a large spoon or a spatula, push some of the beef mixture toward the side of the pan, creating a gap that allows you to slide lasagna sheets underneath the beef. Break about two lasagna sheets in order to fill in the cracks.
7. Step
Top the beef mixture with the rest of the lasagna sheets. Spread the rest of the marinara sauce on top of the sheets. Dollop the ricotta on top of the sauce and spread evenly.
8. Step
Sprinkle the mozzarella cheese over the ricotta, and top with the basil.
9. Step
Bake for 25 minutes until cheese is bubbly and golden brown.