Prep: Wash and dry all produce. Bring 3 cups salted water to a boil in a medium pot. Trim the ends of the scallions, then thinly slice. Trim the ends of the green beans, then cut into 1-inch pieces. Core, seed, and thinly slice the bell peppers. Mince or grate the garlic. Add the rice to the boiling water, cover, and reduce to a low simmer for 15-20 minutes, until tender.

Prep the lemongrass: Trim the ends of the lemongrass, then peel off the outer layers until you get to a rubbery core. Finely mince the core.

Cook the steak: Toss the steak tips in a medium bowl with the cornstarch and a large pinch of salt and pepper. Heat a drizzle of oil in a large pan over high heat. Add the steak to the pan and cook for about 1 minute per side, until browned but not yet cooked through. Remove from the pan and set aside.

Start the stir-fry: Heat another drizzle of oil in the same pan over medium heat. Add the garlic, lemongrass, and scallion whites and cook, tossing for about 2 minutes, until softened. Add the green beans and peppers and cook, tossing for 5-7 minutes, until softened. Season with salt and pepper.

Finish the stir-fry: Add the steak, soy sauce, 2 Tablespoons vinegar, 3 Tablespoons water and 1 Tablespoon sugar to the pan. Cook, tossing, for 1-2 minutes, until the sauce has thickened. Taste and season with salt and pepper.

Serve: Fluff the rice with a fork. Serve the stir-fry over the rice, garnish with scallion greens, and enjoy!