Prep the chicken: Cut the chicken into 8 pieces and pound the pieces until they are thin (for quick cooking) and have expanded in surface area (for more filling). Place the breadcrumbs in a shallow bowl with 2 tablespoons of Parmesan cheese and set aside.
Prep the filling: Chop the spinach and saute it with the garlic and just a drizzle of olive oil for 2-3 minutes or until just barely wilted. Combine the sauteed spinach with the ricotta, Parmesan cheese, and 2-3 tablespoons of the egg whites. Place the remaining egg whites in a separate shallow bowl and set aside.
Assemble the chicken: Oil the bottom of a large baking dish and preheat the oven to 450 degrees. Place one piece of chicken on a flat working surface. Put a spoonful of ricotta-spinach filling right in the middle and roll the chicken up so that the edges meet to form a “seam”. Dip the entire chicken roll in egg whites, and then roll it in the breadcrumbs. Place in a baking dish, seam side down. Repeat for the remaining 7 pieces of chicken. Bake for 25 minutes.
Finishing touches: After 25 minutes, the chicken should be cooked through (white on the inside) and browned on the top. Cover the chicken with the marinara sauce and slices of fresh Mozzarella. Bake for another 3-5 minutes or until cheese is melting. Sprinkle with fresh basil.