I was told to cook beef and bison the exact same. I normally fry the steaks in a frying pan about 5 minutes on each side and let rest to cook the rest of the way. When I do this for bison steaks it turns out that it gets really tough on the outside. Most online references advise to cook on the grill which is not really a possibility for me since it's in the middle of winter. How to I fry bison steaks without it getting tough?
I've usually found Bison Burgers, and other things made from Bison to be "drier" than it's beef cousin.
Try, instead, a high-heat quick sear - no more than 30-45 seconds on each side, and then finish in the oven at a lower temperature. Let your pan heat up as hot as it can go before dropping in your steak. Cast iron is best for this since it'll lose less heat once the meat goes in. Make sure to have a little bit of oil on your steak, canola oil working best with the high-heat.
This will still build the crust from the sear, and the lower temperature of the oven will then be allowed to penetrate the meat more slowly, hopefully losing less juices. You may need to play with the timing, and heat, start with 1-2 minutes on each side, at 450-500*F
Always loosely cover with foil and allow to rest ~5 minutes before cutting. I like to put my meat on a wire mesh rack, or an upside-down plate to help preserve the crust. Also, always cut across the meat grain, instead of with the grain. This will help make for more tender bites.
It may also be worth trying wet-aging/marinading your Bison steaks before cooking. Stab it with a fork on all sides, and put into a double-bagged (to prevent leaks) zipper plastic bag with your favorite marinade for 1-2 days.
You may also try pounding the steak a bit with a meat tenderizer (fancy hammer) or stabbing with a fork to help break down protein linkages in the meat, which will result in a more tender texture.
Water Buffalo if sliced 1/2 inch thick and soaked in beer over night will make it tender. Bison. Rub a Pappia on it both sides and let it set 4 hours will make it tender and a sweeter taste. Sear both sides first when cooking.