Very good! You can use the same dish for marinating and baking; just let it stand at room temperature for 5 minutes on its way from refrigerator to oven.
Place the ribs in a shallow baking pan. Rub the meat tenderizer into the ribs, if using. In a small saucepan, mix together the sugars, vinegar, soy sauce, garlic powder, and chicken broth. Heat to just boiling. Pour over the ribs. Cover and refrigerate overnight.
Preheat the oven to 325 degrees F. Bake the ribs and liquid for about 1 hour, turning the meat once.