1Stir together the soy sauce, canola oil, sesame oil, half the ginger and garlic in a zip-lock bag or bowl; add the steaks and turn to coat. Let them sit for at least half an hour, or refrigerate overnight.
2In a small saucepan, whisk together the rice vinegar and sugar and bring to a simmer; add the ginger and red pepper flakes and remove from heat. In a medium bowl, toss together the cabbage and green onions. Drizzle the warm vinegar mixture overtop and toss to coat.
3Preheat your grill and grill the steaks to your desired doneness - 4-5 minutes per side for medium-rare. Let rest for at least 5 minutes before slicing thinly against the grain and serving atop (or alongside) the slaw.