1. Preheat oven to 325 degrees.
2. Pound chicken between two sheets wax paper to 1/4 inch thickness.
3. Spread a couple of tablespoons of sauce in a baking dish. Place chicken on top and sprinkle with oregano. Pour remaining sauce evenly over chicken.
4. Cover with foil and bake chicken in oven about 20 minutes.
5. Sprinkle parmesan cheese over top of chicken, return to oven uncovered and bake 5 minutes longer or until cheese is melted and chicken is cooked through.