Beef Udon Noodle Stir-Fry

3. Combine and Finish

1. Make Sauce: In a small bowl, whisk together all the sauce ingredients (soy sauce, oyster sauce, brown sugar, rice vinegar, and water/broth).
2. Combine: Return the cooked beef to the wok. Pour the sauce over the vegetables and beef, tossing quickly to coat. Let the sauce bubble and thicken slightly (about 30 seconds).
3. Add Udon: Add the cooked, drained Udon noodles to the wok. Toss everything vigorously with tongs until the noodles are thoroughly coated in the dark, glossy sauce (as shown in the photo).

4. Serve

1. Transfer the Udon noodles to a bowl.
2. Garnish with the remaining green parts of the scallions and a sprinkle of toasted sesame seeds.
3. Serve immediately with chopsticks.