For bright green broccoli, start by blanching the broccoli in boiling water for 2-3 minutes until it turns bright green. Remove, drain under cold water, and pat dry. This step can be skipped, but broccoli won’t be as bright green. Start by slicing the flank steak into thin pieces. For easier slicing, place the steak in the freezer for 10-15 minutes before slicing. Season the beef with pepper.