In a bowl, mix together the ricotta cheese, spinach and Parmesan cheese together.
Make sure your spinach is squeezed completely dry.
Place boneless chicken breasts on top of waxed paper and lightly pound them with the flat side of a meat mallet until the chicken is even in thickness.
Spread some of the cheese/spinach mixture on top of each chicken breast.
Roll each chicken breast up and secure with toothpicks if needed.
Spread a layer of marinara sauce in the bottom of a baking dish that has been sprayed with cooking spray.
Place each chicken breast in the baking dish seam side down.
Sprinkle each chicken breast with the Italian seasoning, salt and pepper.
Bake in a 375 degree oven for about 30 minutes or until the internal temperature of the chicken reaches 165 degrees.
Notes
You can brush a little olive oil on top of each chicken breast before sprinkling the seasonings if you desire.