Spicy Chicken Lo Mein

Name: Spicy Chicken Lo Mein
Ingredients: ⅔ cup low-sodium soy sauce; 3 garlic cloves, minced; 3 tbsp sugar; 2 tbsp oyster sauce; 2 tsp toasted sesame oil; 2 tsp powdered ginger; 2 tsp Sriracha, plus more to taste; 1 lb Chinese egg noodles or spaghetti; 1 tbsp canola oil; 1 medium onion, cut into ¼-inch thick slices; 2 lbs boneless skinless chicken thighs, cut into ½-inch cubes; 1 red bell pepper, thinly sliced; 2 carrots, thinly sliced; 2 celery stalks, diagonally sliced; 1 (5-ounce) can sliced water chestnuts