For the mushrooms and marinade
1 ½ Tbsp coriander seeds
1 sprig thyme
75g olive oil
½ onion, peeled and diced
375g dry white wine
juice of ½ lemon
200g tomato passata
75g tomato puree
30g tomato ketchup
salt and freshly ground black pepper
6 King oyster mushrooms
To prepare the scallops
reserved mushrooms and marinade
Make the mushroom marinade by wrapping coriander seeds and thyme in a secure muslin sachet. Heat the olive oil in a pan and add the sachet and onions. Sweat the onions over moderate heat until completely softened and translucent. Add the wine and lemon juice and reduce the mixture by half. At this time, add the passata, tomato puree and ketchup and simmer for 2 minutes. Remove from the heat and allow to cool. Season with salt and freshly ground black pepper. Trim and clean the mushrooms and cut in half. Add to the cooled marinade mixture and place in the fridge, covered, for 24 hours.
To prepare the scallops, remove them from the shell and discard the skirt and roe. Wash the scallops in cold water and pat dry with kitchen paper. Scrub the shells thoroughly and reserve for use later. Season the scallops with salt and freshly ground black pepper and drizzle lightly with olive oil.
Preheat the Force BBQ with only one of the grills turned on high. Grill the scallops for 30 seconds on each side on the hot grill, then remove and set aside to cool. Remove the mushrooms from the marinade allowing the excess to run off. Season the mushrooms with salt and freshly ground black pepper and cook on the hot grill for 2 minutes each side. Remove from the grill and close the lid, allowing the temperature of the BBQ to rise to 180°C.
Once the scallops have cooled, place each one into the deeper half of the reserved shells. Top with a spoonful of the tomato marinade and place the remaining shell half on top. Roll out the shortcrust pastry and cut into strips. Use these strips to seal the shell shut, ensuring there are no gaps.
Place the sealed scallops on the cool side of the grill and leave there for 12 minutes still at 180°C, adding the mushrooms to the cool side in the last 8 minutes to thoroughly reheat. Remove both the scallops and the mushrooms from the BBQ and rest for 2 minutes before cracking open and discarding the pastry strips from the scallop shells. Season the baked scallops with lemon juice and serve the mushrooms alongside.