Bass groper with fish milk, green tomato and potato paper

1.For pickled green tomatoes, simmer verjuice in a saucepan over medium-high heat until reduced to 1 tbsp (5-6 minutes). Place tomatoes over a flame to blister skin, or use a blowtorch, then peel the tomatoes, cut in half and place in a Cryovac bag with reduced verjuice. Cook the tomatoes in a water-bath at 85C for 8 minutes and then set aside in bag for 5 minutes before dropping them into ice water. Once tomatoes are cooled, set aside at room temperature to mature (1 day), then cut into wedges to serve.

2.Fillet fish and split along the spine to create two loins per fillet (you can ask your fishmonger to do this). Cut away bloodline and reserve bones and trimmings for the sauce. Refrigerate fillets until required.

3.For fish milk, preheat oven to 180C. Combine 180ml hot water and 2 tsp fine sea salt in a bowl, then refrigerate to chill (1 hour). Slit the mullet roe sacks and massage their contents into the cold salt brine, then stir with a whisk to separate the smaller membrane from the roe. Refrigerate the roe in the brine to bloom (3 hours). Strain through a coffee filter or double piece of muslin placed over a sieve and set aside. Chop the reserved bones and trimmings into 4cm chunks. Heat oil in a shallow frying pan, add bones and trimmings in batches and shallow-fry until golden (2-3 minutes per side), then roast in oven in a roasting pan until golden brown (30-40 minutes). Drain off the fat and discard. Combine roasted bones, milk and white soy in a Cryovac bag, seal and cook in a 60C water-bath for 1½ hours. Strain through a fine strainer, discarding solids, then, while still hot, blend milk and xanthan gum with a hand-held blender to a thick cream consistency.

4.Smoke the fish with the roe in a cold smoker (5 minutes; see note), then refrigerate.

5.Meanwhile, heat the milk sauce, then gradually whisk in the smoked mullet roe.

6.Heat a frying pan over high heat, add diced butter and whisk occasionally until golden brown (3-4 minutes). Add white soy and set aside to cool to room temperature, then blend with a hand-held blender to combine. Set aside.

7.Season the fish with sea salt, cut into 70gm portions and place in Cryovac bags. Add 2 tsp of soy butter to each bag and refrigerate. Once the butter has set, seal bag and cook in a 48C water-bath until fish starts to flake (16-18 minutes).

8.For sea parsley oil, pick the sea parsley and blanch in salted water (3 minutes), then refresh in ice water. Once fully cool, drain the parsley and squeeze it firmly in a clean tea towel to remove all excess water. Blend with grapeseed oil in a Vitamix blender on the highest speed until the mixture gets hot, and quickly cool in a bowl placed over ice. Drain through an oil filter and set the green oil aside in a small squeeze bottle.

9.For potato paper, preheat oven to 60C and boil potato in salted water until tender (20-25 minutes). Blend with 2 tsp cooking water in a small blender until smooth. Season with salt to taste and pass through a fine strainer. Spread mixture very thinly (1mm) and evenly with a spatula on 2 large Silpat mats (or oven trays lined with baking paper), pressing firmly once cool, and dehydrate in the oven until completely dried (4-6 hours). Once the papers are fully dry they should easily detach from the sheets. Store in an airtight container. Heat vegetable oil in a deep-fryer to 160C, then fry potato sheets in oil, turning over halfway, until starting to turn golden (2-3 minutes). Just before serving, break into shards.

10.To serve, pour a small amount of fish milk onto each plate (you’ll have some remaining), top with fish (slightly separated), green tomatoes, a few drops of sea parsley oil, sea banana tips and potato paper shards.