Preheat oven to 350 F. Lightly coat a baking sheet with cooking spray.
In a large, nonstick frying pan, heat the olive oil over medium-high heat. Add the chicken and saute, turning every now and then until golden brown — about 10 to 12 minutes. Set aside to cool. When cool to the touch, cut the chicken breasts into cubes. Set aside.
In a small bowl, combine the spinach, ricotta cheese, garlic, parsley, Parmesan cheese and 1 of the egg whites. Mix until well blended. Set aside.
In another bowl, use a wire whisk or fork to lightly beat the remaining egg white.
Cut the bread dough into 6 equal-sized pieces. On a floured surface, press each piece into a circle. Using a rolling pin, roll each dough piece into ovals 8 inches long and 6 inches wide. Brush the edges of the dough ovals with the lightly beaten egg white.
Place 1/6 of the chicken cubes in the center of each oval. Add 1/6 of the spinach mixture to each. Fold the dough over the filling, pressing the edges together. Crimp with a fork and place on the prepared baking sheet.
Bake until browned and crispy, about 15 to 20 minutes. Serve right away.