You’ll never eat another version of this recipe after tasting this meat. In a bowl, combine the soy sauce, rice wine (or sherry), and cornstarch. Add the thinly sliced meat and stir to combine. Allow it to marinade for around 15-20 minutes.
In a large skillet or wok, heat 1 tablespoon vegetable oil over high heat. Stir in the marinated beef and cook for 2-3 minutes, until browned. Remove the steak from the skillet and put aside.
In the same skillet, add the remaining tablespoon of oil. Stir-fry the sliced onion and bell pepper for 2-3 minutes, until slightly softened. Add the minced garlic and ginger to the skillet and cook for another 30 seconds until fragrant.
Return the cooked beef to the skillet, along with any accumulated juices. Combine sugar, beef broth (or water), oyster sauce, and soy sauce. Stir everything together and allow it simmer for 2-3 minutes.