In a large bowl combine steak, potatoes, olive oil, salt and pepper, garlic, and seasonings and toss to combine.
Divide steak and potatoes between four 12x12 inch sheets of foil, then wrap the foil tightly around the contents to form your foil packs.
Grill over high heat for about 10 minutes on each side or until steak and potatoes are cooked through OR bake at 425 degrees for about 20-25 minutes until cooked through to desired doneness (see note).
*If you prefer a char on your steak, you can open up the packets at the end and cook for a couple minutes directly on the grill, or for baking you can switch oven to broil for a few minutes (with packets opened).
Be sure to cut your steak into pieces that are at least 2x2 inches, and potatoes into pieces smaller than one inch. This ensures even cooking.
**For medium doneness on the steak, boil the potatoes first for five minutes before adding to the bowl and proceeding with the rest of the recipe. This will help them to cook faster once in the foil pack.