01 - Heat a large, deep skillet over medium heat. Cook the ground beef or sausage until browned, breaking it up with a wooden spoon. Drain excess fat if needed.
02 - Add the diced onion to the skillet and cook for 3 to 4 minutes until softened. Stir in the minced garlic and cook for 1 minute until fragrant.
03 - Pour in the crushed tomatoes and add the tomato paste, dried oregano, dried basil, red pepper flakes, salt, and black pepper. Stir well to combine all ingredients.
04 - Add the broken lasagna noodle pieces to the sauce, submerging them completely. Pour in 1/2 cup of water if the sauce appears too thick.
05 - Cover the skillet and reduce heat to medium-low. Simmer for 15 to 18 minutes, stirring occasionally, until the noodles are tender.
06 - Drop dollops of ricotta cheese evenly across the surface of the lasagna. Sprinkle the shredded mozzarella and grated Parmesan over the top.
07 - Cover the skillet and cook for an additional 3 to 5 minutes until the cheese has melted completely and bubbles around the edges.
08 - Remove the skillet from heat and let it sit uncovered for 5 minutes to set. Garnish with fresh basil or parsley if desired. Serve warm.