Start by preparing the ricotta cheese mixture. In a medium bowl combine the ricotta, shredded mozzarella, grated parmesan, egg, and black pepper. Mix together until well combined and set aside.

Next, remove the skin from the cooked rotisserie chicken and pull the meat off of the bones. Shred the chicken using two forks.

While you are preparing the chicken, bring a large pot of water to a boil over high heat. Add 1/2 Tbsp of salt to the water then add the lasagna noodles and boil until the pasta is tender (or al dente). Drain the pasta in a colander.

Preheat the oven to 375. Then in a large skillet, melt the butter over medium heat. Add the diced onion and minced garlic. Sauté for 4 minutes or until the onion is translucent.

Stir in the flour and cook until the flour starts to turn light brown. Now slowly pour in the chicken broth and whisk the broth with the flour mixture until combined.

Add the Italian seasoning, 1/2 tsp salt, 1/4 tsp black pepper, garlic powder, heavy cream, and 1/4 cup grated parmesan cheese to the sauce. Stir to combine. Now add the chopped spinach to the sauce and stir to combine.

Time to assemble the lasagna. Spread about 1 cup of the sauce over the bottom of a 9x13-inch casserole dish. Lay three noodles on top of the sauce.

Spread 1/3 of the ricotta cheese mixture evenly over the noodles. Then top with 1/3 of the shredded chicken. Repeat the layers (sauce, noodles, ricotta, chicken) two more times.

Finish with the remaining sauce, then top with 1 1/2 cups of shredded mozzarella.

Bake the lasagna in the preheated oven for 25 minutes until the cheese is fully melted on top. Switch the oven to broil for the last 3-4 minutes or just until the cheese gets a little brown on top.

Top with chopped parsley if desired, and slice into nine pieces. Serve and enjoy!