Spiced Butternut Squash Soup with Toasted Sunflower Seed Miso Ice Cream

STEP 1: MAKE THE SUNFLOWER SEED MISO (THREE MONTHS AHEAD)

Toast the hulled sunflower seeds dark in a dry pan until they smell of praline rather than of burning; this deep toast is the whole flavour of the dish, so do not stop short. Cover with water and simmer for 45-60 minutes until a seed crushes to a paste between finger and thumb, then drain, keeping the liquor, and cool below 40 C. Blend the seeds coarsely, work in the crumbled koji and the salt by hand, and loosen with the reserved liquor to a stiff paste that holds its shape. Pack tight into a crock with no air pockets, weight the surface, cover, and ferment at 20-25 C for at least three months, until dark, savoury and faintly sweet. At short notice, blend 400 g toasted sunflower seed butter with 120 g shiro miso, 20 g rice vinegar and 30 g water and label it as the substitute it is.

STEP 2: PRESERVE THE SUNFLOWER HEARTS (AT LEAST 48 HOURS AHEAD)

Strip the bracts from the immature sunflower heads, scoop out the hairy choke, halve the hearts and drop them into acidulated water as you go. Bring the water, salt, vinegar, caster sugar and bay leaf to the boil, pour over the hearts, cool and refrigerate for at least 48 hours. Keep the liquor - the vinaigrette needs it.

STEP 3: MAKE THE ICE CREAM BASE

Warm the oat milk to 55 C. Whisk in the caster sugar, glucose syrup, salt and the two gums, then blend hard for a full minute so the gums hydrate completely; gums added to a cold or fatty base never hydrate properly. Blend in the sunflower seed butter, the miso and the oil until perfectly smooth, pasteurise at 80 C for two minutes, then chill over ice and mature for 12 hours at 4 C.

STEP 4: CHURN AND SHAPE THE ICE CREAM

Churn the matured base and freeze it in a shallow tray at -18 C. Shape into six 55-60 g quenelles and hold them at -11 C rather than -18 C: the gums hold the shape, and the warmer ice cream draws far less heat out of the soup. This is the single biggest lever on the hot-and-cold balance of the plate.

STEP 5: MAKE THE SEED CRUMBLE AND COAT THE QUENELLES

Toast the sunflower seeds, toss them with the miso, oil and salt, spread out and dry at 140 C for 10 minutes, then break to a coarse crumb. Roll each quenelle in the crumb, pressing on a visibly thicker shell than looks necessary - that shell is the insulating layer that lets the ice cream melt into the soup rather than against it. Hollow the top of each coated quenelle with a warmed parisienne scoop and return them to -11 C. If the crumb slides off, let the quenelle come up for 90 seconds, press the crumb on firmly and return it to the holding temperature.

STEP 6: MAKE THE VINAIGRETTE AND FILL

Blanch the young sunflower leaves for 8 seconds and refresh. Blend them with the petals, the preserving liquor from the hearts, the oil and the vinegar to a loose green vinaigrette and season. Fill each hollowed quenelle at the last moment.

STEP 7: BUILD THE SOUP

Sweat the shallots, deseeded chilli and garlic gently in the vegan butter with the ground coriander seeds, cumin seeds, fennel seeds, mace and a good pinch of salt, taking no colour. The chilli goes in at the start, as it was cooked, and stays gentle - the warmth should sit behind the squash, not in front of it. Add the squash and cook it down into the aromatics until it begins to break, then add the stock and simmer until completely tender.

STEP 8: INFUSE, BLEND AND HOLD THE SOUP

Off the heat, add the lemon verbena, cover and infuse for 10 minutes, then lift the leaves out - longer or hotter and the verbena turns soapy. Blend smooth, pass through a fine chinois and season. Bring the soup back to 88 C and hold it there. Warm the serving jug with boiling water and dry it before filling, and warm the bowls to 60 C; a cold jug and a cold bowl will strip 15-20 C before the spoon ever moves.

STEP 9: MAKE THE TEAR-AND-SHARE BREAD

Mix the flour, water, oat milk, yeast, miso and oil to a shaggy dough and rest for 20 minutes, then add the salt and work to a strong, smooth dough. Bulk-ferment for 90 minutes with two folds. Divide into 40 g balls, arrange them touching in a lined tray and prove until puffed and joined. Bake at 220 C for 8 minutes, then brush with the glaze of miso, maple syrup and oil, scatter with sunflower seeds and bake a further 8-10 minutes until deeply glazed and crisp. Glaze at the halfway point, not the start, or it will burn before the crumb sets.

STEP 10: MAKE THE SUNFLOWER SEED MISO BUTTER

Blend the oat milk, miso, lecithin and salt, then stream in the melted coconut oil and the sunflower oil slowly with the blender running to a stable emulsion; too fast or too warm and it will split. Set in a mould at 4 C and bring it to 16 C to serve, so it spreads.

STEP 11: TO SERVE

Set a filled, crumbed quenelle slightly off-centre in each warmed bowl, arrange the preserved sunflower hearts over it like petals and finish with fresh sunflower petals. Take the warm bread and the butter to the table with the hot jug, and pour 150 ml of soup around the ice cream in front of each guest. Check three numbers before service: soup at 88 C, bowls at 60 C, ice cream at -11 C.