Turn a grill on medium heat. Cut one large cabbage from top to bottom into 4 steaks. Combine salt, pepper, and garlic powder into 2 tablespoons of olive oil. Mix then apply to each side of the cabbage steaks. Put steaks on the grill, cooking each side for 10-15 minutes. Your cooking time may vary depending on the exact temperature of your grill and how tender you would like the steaks to be. Remove from the grill and serve alongside green goddess dressing* (see below).
Dressing:
Combine all the green goddess dressing ingredients in a food processor and pulse to combine. Taste and add more salt or lemon juice as desired. Add more greek yogurt to thicken; add a small amount of water to thin it. Once made, store in a refrigerator until ready to serve.