The pictures pretty much sum it up. Here is what you need
spray butter substitute (if you are going extremely healthy you could just add a touch of water to each packet)
salt and pepper
garlic powder (or minced garlic depending on how much you like garlic)
red pepper flakes (optional)
aluminum foil (heavy duty is the best but I'm cheap and usually just handle the regular stuff delicately)
Remove outter leaves of cabbage and start by quartering the cabbage and cutting the core out of each quarter. Now cut each quarter in half again so you have 8 sections of cabbage.
Tear off 2 pieces of aluminum foil long enough to lay out 4 of the 1/8 slices and fold back over so you only have to seal 3 sides of the foil.
Spray the foil with the "butter" where the 4 slices will sit. Arrange the 4 slices on the butter to one end of the foil (see pic). Then spray the tops and sides with the "butter". Now apply your spices (I'm liberal with the black pepper and garlic powder...but depending on your tastes a little red pepper goes a long ways in this application). Once seasoned seal you packet (see pic) and repeat for the other packet.
Now on a medium-high to high grill put your packets on for 10 minutes per side. (be careful flipping the packets with tongs because this is where you can rip the foil and lose your steam cooking) Remove from grill and ENJOY!
We like our cabbage to retain a little crunch and generally that timing acheives that. If you like cabbage softer play with the timing. You can unroll one edge and sample until you get the desired doneness. Just make sure to check the leaves that were cloesest to the core because they retain their crunchiness the longest.
I use these foil packets for all sorts of stuff on the grill....onions, onions and peppers, mushrooms, brussel sprouts, fresh snapbeans (greenbeans for those not from the south)...as always take the idea and make it your own.