supreme soy sauce chow mein

Name: supreme soy sauce chow mein
Ingredients: 1 tablespoon water; 1 tablespoon light soy sauce (or more, to taste); 1 tablespoon dark soy sauce; 2 teaspoons oyster sauce or vegetarian stir-fry sauce; 2 teaspoons sesame oil, plus more to finish; 1 teaspoon sugar (or more to taste); 7 ounces dried or 14 ounces fresh thin egg noodles (here are two options that were available at the 99 Ranch near me); 3 tablespoons vegetable or other neutral oil; ½ cup scallions, finely sliced (from about 4-6 scallions); ½ cup thinly sliced onions (from about ½ medium onion); 2 cups (about 6-7 ounces) bean sprouts; 2 tablespoons toasted sesame seeds; Salt and pepper, to taste