-
1
Preheat a gas grill or prepare a fire in a charcoal grill. Place a piastra on the grill to preheat.
-
2
Slice the tomatoes creatively (leave very small ones whole, or halve them) and layout on a platter. Tear the basil leaves over the tomatoes, strewing them about. Set aside.
-
3
Season the onion slices on both sides with salt and pepper. Place them on the hot dry piastra and cook, unmoved, for 7 to 10 minutes, until well charred on the first side. Using tongs, carefully turn the slices over and cook for 7 to 10 minutes on the second side, until well charred and softened. Transfer to a plate and let cool slightly, then separate the onion slices into smaller rings and scatter them over the tomatoes. Drizzle the whole mess with 3 to 4 tablespoons of the olive oil.
-
4
While the onions cook, carve a checkerboard pattern about 1/4 inch deep into one side of each scallop. Season the scallops all over with salt and pepper, toss them in a bowl with the remaining 2 tablespoons oil, and stir gently to coat.
-
5
Place the scallops on the dry clean piastra, design side down, and cook for 5 to 7 minutes, unmoved, until almost cooked-they should be opaque almost all the way through. Flip them over and sear for just 30 seconds, then remove and arrange on the tomato salad.
-
6
Sprinkle the scallops and tomatoes with Maldon salt, squeeze the lemon halves over them, and serve.
