DO-AHEAD TIP: Marinate seasoned beef for at least 30 minutes or up to 2 hours (see recipe).
In a large bowl, place first 6 ingredients (beef through chili powder); toss well to coat. Cover and refrigerate for at least 30 minutes or up to 2 hours.
Heat the sesame oil in a large skillet or wok over medium heat. Add gingerroot and garlic; cook for 1 to 2 minutes or until soft and fragrant. Raise skillet (or wok) heat to medium-high.
Add beef; cook, stirring occasionally, for 4 to 5 minutes or until browned. Stir in broth and fish sauce; bring mixture to a boil then reduce heat to low, partially cover and cook for 25 to 30 minutes or until beef is tender and liquid has thickened.