Cook lasagna noodles per package directions. Drain and set aside.
Preheat oven to 375 degrees F.
Squeeze all the water out of the spinach. Best way to do this is squeezing by hand I take small handfuls at a time and really squeeze the heck out of it. Place squeezed spinach in a. large bowl.
Add the ricotta, shredded cheeses, salt, pepper and chicken to the spinach and blend well. Add the beaten egg and mix thoroughly.
Place about 1/2 cup of any sauce you use in the bottom of an 11 x 7-inch baker; spread across the bottom.
Place about 1/3-1/2 cup of the spinach mixture onto each lasagna noodle, spreading it out and leaving about 1/2 inch at one end of the noodle without any filling. Roll up, rolling towards the unfilled end. Place seam side down in prepared pan. Repeat.
Pour remaining sauce over rolls in pan, taking care to cover the tops of the rolls with sauce. Distribute the 1/2 cup of mozzarella for topping evenly over rolls.
Cover dish with aluminum foil and bake at 375 degrees F for 30-40 minutes.