Skillet Lasagna

Preheat the oven to 425 with a rack in the top third. In a large pot of boiling, salted water, cook noodles, stirring a few times until al dente, about 6 minutes. Drain.

Meanwhile, wrap thawed spinach in a clean kitchen towel and wring out as much excess liquid as possible. Transfer to a medium bowl and combine with ricotta, Parmesan, 1 teaspoon of salt, and ¼ teaspoon of pepper.

Heat oil in a 10-inch, high-sided, ovenproof skillet over medium-high. Add beef and season with salt and pepper; break up into small pieces with a wooden spoon and cook, turning a few times, until meat is browned, about 8 minutes.

Drain excess fat from skillet and scrape browned beef into a large heatproof bowl. Set aside 1 ½ cups sauce and stir the remaining marinara into the bowl with browned beef.

Using the same skillet, (do not return to the heat) spread about 1 cup of the sauce mixture in a thin layer at bottom of skillet. Arrange a third of the noodles over the sauce, breaking the noodles up to fit if necessary, and spread half of the remaining sauce mixture over the noodles.

Spread on half the spinach-ricotta mixture and sprinkle with a third of the mozzarella. Repeat layering one time with another third of the noodles, the remaining half of the meat sauce mixture, the remaining half of the spinach-ricotta and another third of the mozzarella.

Top lasagna with remaining third of the noodles. Spread atop that reserved marinara sauce you earlier set aside. Sprinkle with remaining third of the mozzarella. Bake lasagna until golden and bubbly, about 25 minutes.

Let sit 10 minutes before serving. Sprinkle with Parmesan. Cut leftovers into slices and wrap in plastic to freeze. Rewarm individual slices in microwave by first defrosting and then heating on high for 2-3 minutes.