Beef and Broccoli with Red Peppers

Combine rice, salt, and 2 1/4 cups water in a medium-sized pot with tight-fitting lid. Bring to a boil, then reduce heat to low and simmer, covered, until all water is absorbed, 15 minutes. Turn off heat and let sit 10 minutes (no peeking!). Remove lid and fluff with a fork. Meanwhile, in a medium bowl, whisk together soy sauce, chicken broth, rice wine vinegar, brown sugar, garlic, sesame oil, cornstarch, ginger, and Sriracha. Heat oil in a large deep-sided skillet. Cook steak in batches until nicely browned, about 4 minutes. Transfer to a plate. Add remaining oil to skillet along with broccoli and red pepper and cook until broccoli is bright green, 1 to 2 minutes. Add 1/2 cup water and let steam, covered, until vegetables are tender-crisp, 2 to 3 minutes. Add sauce and steak to skillet and bring to a boil. Let simmer until thickened, 3 minutes more. Serve beef and broccoli with cooked rice and garnish with crushed red pepper, if using.