Use a fork and poke holes all over the surface of your steaks. Place steaks in large baking dish. In a bowl, mix together beer, teriyaki sauce, and brown sugar. Pour sauce over steaks and let sit about 5 minutes. Sprinkle with 1/2 the seasoning salt, pepper and garlic powder, set aside for 10 minutes. Turn steaks over, sprinkle with remaining seasonings and continue marinating for 10 more minutes.
Your steaks are now ready for grilling! Enjoy!