Heat a medium nonstick skillet over medium-high heat. Coat pan with cooking spray. Add potatoes, bell pepper, and onion to pan; sauté 4 minutes or until onion begins to brown, stirring frequently. Add sausage; cook 4 minutes or until browned, stirring to crumble. Stir in spinach; cook 2 minutes or until spinach wilts. Stir in basil, salt, and crushed red pepper. Remove from heat.
Cut dough into 4 equal portions. Roll each portion into a 5-inch circle. Spoon about 1/2 cup potato mixture on half of each circle, leaving a 1/2-inch border. Fold dough over potato mixture until edges almost meet. Bring bottom edge of dough over top edge; crimp edges of dough to form a rim.
Place turnovers on a baking sheet coated with cooking spray. Combine 2 tablespoons water and egg white in a small bowl, stirring with a whisk; brush evenly over dough. Sprinkle about 2 teaspoons cheese over each turnover. Bake at 400° for 18 minutes or until golden brown. Let stand at least 5 minutes before serving.