In a bowl, combine the thinly sliced flank steak with soy sauce, oyster sauce, rice vinegar, and a pinch of salt and pepper. Let it marinate for at least 20 minutes.
Rinse the jasmine rice under cold water until the water runs clear. In a medium saucepan, combine the rinsed rice and beef broth. Bring to a boil, cover, and reduce heat to low. Cook for about 15 minutes or until the rice is tender and the broth is absorbed. Fluff with a fork and set aside.
Toss the marinated beef with cornstarch until well-coated. In a large skillet or wok, heat the vegetable oil over medium-high heat. Add the beef in batches, ensuring not to overcrowd the pan. Fry until crispy, about 3-4 minutes per side. Remove and set aside on a paper towel to drain excess oil.
In the same skillet, add garlic, ginger, and red chili flakes. Sauté for about 30 seconds until fragrant. Add the sliced bell peppers and stir-fry for about 2-3 minutes, or until just tender but still crisp.
Add the crispy beef back to the skillet with the peppers. Stir everything together and sauté for another minute to combine the flavors. Taste and adjust seasoning if necessary.
Place a generous scoop of the fluffy jasmine rice on a plate, then top with the crispy chili beef mixture.
Notes
Garnish with chopped scallions and serve with lime wedges for added zest.