*Directions

Make the sauce: In a medium bowl, whisk together the soy sauce, vinegar, sugar, and cornstarch. sit aside.
In a large skillet over high heat, heat 1 tablespoon of the oil. Add the sirloin, season with salt, and cook until cooked through and seared on all sides, about 8 minutes. Remove steak to a plate.
Add 1 tablespoon of the remaining oil and the red and green peppers to the skillet. cooking to soft, for 4 min. Adding garlic & ginger and cook, stir, until fragrant. Return the beef to the skillet and pour over the prepared sauce. Cook, stirring, until sauce is glossy, 2 more minutes.
Served with rice.

Enjoy !