Drop the pieces of sweetcorn into a pan of boiling salted water and cook for 5-6 minutes until tender. Drain well and set aside.

Cut the lobster tails in half lengthways and pull out and discard the dark grey thread running along its length. Put the lobster, prawns, sweetcorn pieces, tomato halves, olive oil, lemon juice, half of the thyme and some freshly ground black pepper into a mixing bowl and toss together well. Rub either side of each piece of steak with a little more oil, sprinkle with the remaining thyme and season with pepper.

Put the ingredients for the herb butter into a small pan and melt together over a low heat. Set to one side.

Heat the dry grill pan over a medium heat for a few minutes until hot. Add the pieces of lemon, flesh side down and chargrill for 1 minute on each cut side until marked with the lines of the grill. Remove to a small plate.

Add the pieces of steak to the grill pan and cook for 4 minutes. Turn the steaks over (this will give you steak that is medium-rare) and add the pieces of lobster, cut-side down, the tomato halves and the pieces of sweetcorn to the grill. Cook for 2 minutes more. Turn the lobster, tomatoes and sweetcorn over and add the prawns to the grill. Cook the prawns for 1 minute on each side, continuing to turn the pieces of sweetcorn as they brown.

Once everything is cooked, remove the grill from the heat and drizzle over the herb and garlic butter. Scatter with some sea salt flakes and serve straight away with a green leaf salad and some skinny fries.

Cook's Notes

Cook the food in two batches (half the ingredients first, followed by another batch) on the grill one after the other and adjust the quantities to the number of people and how big the appetites are.

Have your accompaniments for this dish all ready, so that as soon as everything is cooked you can remove it from the grill and serve. If you leave the food on the grill for any longer it will continue cooking because cast iron retains heat very well.