These tender grilled cabbage steaks are topped with store-bought pesto and creamy burrata cheese. The slices closest to the center of each head hold together best with the core keeping them intact. Chop up the leftover outside edges of each head to roast alongside the cabbage steaks, or thinly slice them for a simple cabbage salad.
Preheat grill to medium-high heat. Place 1 cabbage head core-down on a cutting board; cutting vertically, slice 3 steaks (3/4- to 1-inch thick) from the center of the head, keeping the core intact. Repeat with the remaining cabbage head, for a total of 6 steaks. (Reserve remaining cabbage for another use.)
Coat each cabbage steak with cooking spray. Sprinkle with salt and pepper. Grill, covered, until charred on the bottom and starting to soften, 4 to 5 minutes. Flip the steaks; spread pesto evenly over the tops. Cover and continue grilling until soft, 3 to 4 minutes more.
To serve, top each cabbage steak with a wedge of burrata. Sprinkle with basil, if desired.