If it's elk I only cook it one way. I stuff the flank with pork sausage using calamata olive bread. Truss and brown really well at high heat. Then add your own winter type stock and braise. I've paired it with many things but everyone really likes just the sliced stuffed flank, sauced. then just add rustic braised root vegetables on top of a grilled garlic/rosemary polenta round.
We have a lot of deer on our property, so I usually do fajita with the venison flank.
BTW not sure where you got the meat but don't pass up any shanks if they are offered. They are the best!