Thinly slice some white parts of the green onions. Cut the green parts into long strips, about 2 inches (5 cm) long. Keep them separately.
Smash the garlic cloves and finely chop them. Grate a small knob of ginger (2.5 tsp).
Make the sauce. In a small container, mix together the soy sauce, sugar, oyster sauce, chicken bouillon powder, dark soy sauce, corn syrup, Shaoxing wine, black pepper to taste, water, and cornstarch.
In a wok (or pan), heat the oil (1 tbsp) over medium-high heat. Once it gets nice and hot, add the ground beef. Break up the beef and saute for 7 to 8 minutes or until the beef is nicely browned. Remove from the wok and set aside.
To the same pan, add the oil (2 tbsp) and place it over medium heat. Add the white parts of the green onions, garlic, and ginger. Give it a good stir and let all the flavors infuse for 1 minute.
Add thicker parts of the green onions and dried chilies (if using). Stir them around for another 30 seconds. (If you want to make it more fancy or nutritious, you could also add some sliced bell peppers or button mushrooms, too.)
Pour in the sauce. Simmer for 1 minute or until the sauce thickens up a little bit. Add the beef back in and mix together for 1 minute. Turn the heat off. Add the remaining green onions and sesame oil. Give it a final mix.
To serve, put some rice into a bowl and add a generous amount of Mongolian beef. Garnish with sliced red chili (if using). Enjoy!
