TOP SIRLoin cornstarch soy sauce shaoxing wine broccoli carrot red onion red bell pepper mushrooms napa cabbage snow peas grapeseed oil beef stock dark brown sugar oyster sauce sesame oil garlic S&P
Add thinly sliced top sirloin, cornstarch, soy sauce, & rice wine to a medium bowl. Season with white pepper. Stir to combine, coating the beef thoroughly & evenly. Set aside to rest at room temperature while you prepare the rest of the ingredients.
Add beef stock, cornstarch, dark brown sugar, oyster sauce, soy sauce, & 1 tsp. sesame oil to a small bowl or jar. Whisk or shake to combine well. Set aside. Add the remaining 1 tsp. sesame oil to a small saucepan over medium-high heat. Once hot, add garlic & cook until fragrant & lightly browned, 30 seconds – 1 minute. Stir in the beef stock mixture & cook, stirring occasionally, until thickened, 4-5 minutes. Remove from heat & set aside.
Add 1 tsp. oil to a wok or large skillet over medium-high heat. Once hot & shimmering, add carrots & broccoli. Lightly season with salt & cook, stirring often, until vibrantly colored & softened slightly, 3-4 minutes. Transfer to a large plate or bowl. Add another 1 tsp. of oil to the wok over medium-high heat. Add remaining vegetables. Lightly season with salt & cook, stirring often, until softened slightly, about 3 minutes. Transfer to the same large plate or bowl as the broccoli & carrots.
Add remaining oil to the wok or skillet & reduce the heat to medium. Once hot, add the marinated beef. Shake the pan to separate the slices of beef for even browning. Cook, tossing & stirring occasionally, just until browned. While stirring, pour the prepared stir fry sauce into the skillet. Add the stir fried vegetables back into the skillet. Cook 1-2 minutes longer, tossing & stirring frequently. Remove from heat.