Hoisin Beef Noodle Stir Fry

Name: Hoisin Beef Noodle Stir Fry
Ingredients: 1/2 cup reduced-sodium soy sauce; 2 cloves garlic (minced); 3 tablespoons hoisin sauce; 1 tablespoon brown sugar; 1 tablespoon freshly grated ginger; 1 teaspoon sesame oil; 1/2 teaspoon crushed red pepper flakes; 2 teaspoons cornstarch; 2 packages Udon Noodles, Original Flavor (7.34 oz. ); 1 tablespoon olive oil; 8 ounces beef top sirloin filet (thinly sliced across the grain); 2 stalks celery (chopped); 2 carrots (thinly sliced); 6 ounces fresh broccoli florets (cut into bite-size pieces); 6 ounces baby Bella mushrooms (sliced)