Spray a 9x13-inch baking dish with nonstick cooking spray.
In a large bowl, add the shredded chicken, ranch dressing packet, and Buffalo sauce. Using tongs, mix to combine.
In a medium-sized bowl, add the blue cheese, ricotta, and 1 cup of mozzarella cheese. Using a spoon, mix to combine.
Place 1/2 of the chicken mixture into the bottom of the baking dish. Top with 4 lasagna noodles. Cover with 1/2 of the ricotta mixture. Repeat layers of the chicken mixture, lasagna noodles, and ricotta mixture. Top with a final layer of lasagna noodles and 2 cups of the remaining mozzarella cheese.