Place a large cast-iron skillet on top of the grilling grate over the fire pit. Cook the ground beef, onions, italian seasoning, salt, pepper, and garlic until the meat is cooked through. Add the lasagna noodles, tomato sauce, and chicken broth; stir gently to combine. Bring the mixture to a boil and cook for about 10-12 minutes, stirring occasionally to keep the noodles from sticking to the bottom of the skillet. When the noodles are tender, remove the skillet from the fire, and gently stir in the ricotta and mozzarella. Lay 1 sheet of heavy-duty aluminum foil over the top of the skillet and place over the fire again. Once the cheese has melted, remove the skillet from the fire and allow it to cool slightly. Serve with warm bread.