Serves 16 as a tasting-size appetizer

Ingredients

Seaweed crouton

8 thin slices seaweed bread

Olive oil

Salt and pepper

 

Lemon custard

4 cured lemons, quartered

1 lemon

200g heavy cream

1 large egg

1 large egg yolk

 

Seawater

1 small head fennel

10g kombu

33g chopped leek, white part only

12g chopped celery

6g coarse sea salt

¼ piece whole lemon omani

3g nori sheets

 

Glazed fennel coins and oysters

16 kusshi oysters

2 grams vegetable gelatin (carageenan)

 

Avocado mousse

3 ripe avocados

265g water

50g lemon juice

2.5ml tabasco sauce

Salt and pepper

 

To finish

3 sheets gelatin

Canola oil for frying

60g vietnamese rice vermicelli

2 sheets finely diced nori

8 tongues uni (sea urchin), halved

80g golden ossetra caviar

16 pieces oyster leaves

16 yellow celery leaves

 

Method

For the seaweed crouton

Preheat oven to 175c. Cut the bread into a least sixteen 2-cm discs. Lightly brush two silpats with olive oil and set one on a baking sheet, oiled side up. Line the bread discs on top in a single layer, season with salt and pepper, and top with the second silpat, oiled side down. Bake until crisp, about 6 minutes. Cool and store in an airtight container.

 

For the lemon custard

Preheat the oven to 90c. Rinse cured lemon quarters. With a small knife, trim away and discard the flesh and white pith from the peels. Transfer peels to a small saucepan, cover with cold water, bring to a simmer, and then drain.  Repeat process twice, and set aside. With a vegetable peeler, peel long strips from the lemon, and then squeeze and reserve the juice. Trim and discard the white pith from the peels. Transfer the peels to a small saucepan, cover with cold water, bring to a simmer and then drain. Repeat the process 4 more times, and set aside. Roughly chop the cured and regular lemon peel and transfer to a saucepan with the reserved lemon juice. Place over a low heat and cook, stirring until almost all of the juice has evaporated. While still warm, transfer the mixture to a blender and purée with half of the cream until smooth. In a medium sized bowl, whisk to combine the egg, egg yolk, lemon purée and remaining cream, and then pass through a fine-meshed sieve. Divide the custard into 16 small oven safe bowls or ramekins (with the inset diameter no larger than 6-cm) to reach a thickness of approximately ½-cm.  Cover the bowls tightly with plastic wrap and place in a baking or roasting pan with sides deeper than the bowls. Pour hot water into the roasting pan and around the bowls to reach the level of the custard. Bake for 35 minutes or until the custard sets. Unwrap the bowls of custard and chill, flat, in the refrigerator for 2 hours.

 

For the seawater

Trim the fennel, separate the layers and peel the outer sides of the layers.  Using a 2 ½-cm ring cutter, punch out at least 16 ‘coins’ and reserve. Finely chop the remaining fennel trim. In a medium saucepan, bring 750ml of water to a boil, remove from the heat and add the kombu, fennel trim, leek, celery, coarse sea salt, lemon omani and nori sheets. Stir to combine, cover and infuse for 20 minutes. Strain through a fine meshed sieve and discard the solids. Reserve chilled.

 

Glazed fennel coins and oysters

Preheat the oven to 175c. Scrub the oysters well and place cupped side down on a baking sheet lined with crumpled aluminum foil to keep them level. Bake for 2 minutes, remove and then transfer to the refrigerator to chill. Place a bowl over ice and with an oyster knife, remove the top shell of one oyster and run the knife underneath to cut the muscle. Pour the oyster along with its juice into the iced bowl and repeat until all of the oysters are open. Strain the oyster juice through a fine-meshed sieve. Trim away the muscle and outer ruffled edge of each oyster and reserve in the juice, chilled. Bring a large pot of salted water to a boil and place a bowl of ice water on the side. Boil the reserved fennel coins for 20-30 seconds, or until tender, chill in the ice water, strain and pat dry. Measure 250g of the ‘seawater’ into a small saucepan. Bring to a simmer, remove from the heat and whisk in the vegetable gelatin. Cool to 35c. Individually dip the oysters into the gelée to coat, and place one each, slightly off center, on top of each bowl of lemon custard. Dip the fennel coins in the gelée and place one each on top of the custards at an opposite side of the oyster. Return to the refrigerator to set the gelée, about 1 hour.

 

For the avocado mousse

Combine all the ingredients in a blender and purée until smooth. Season to taste with salt and pepper. Pass through a fine meshed sieve, and transfer to the canister of the whipped cream maker. Charge with three nitrogen chargers, leaving the third attached and keep well chilled.

 

To finish

Soak the gelatin sheets in ice water for 10 minutes, remove and squeeze dry. Measure 250g of the remaining ‘seawater’ and pour into a small saucepan. Bring to a simmer and remove from the heat. Add the gelatin sheets and stir to dissolve. Cool to 35c. Carefully pour the gelée on top of the custards, dividing evenly into the bowls. Refrigerate, flat, until set, about 1 hour. Fill a third of a medium saucepan with the canola oil and heat to 400f. Fry the vermicelli so that it expands and crisps. Dry on a paper towel-lined tray and sprinkle with the diced nori flakes. For each portion, place one half of a uni tongue and approximately 5g of caviar onto the custard. Squeeze a dollop of avocado mousse from the whipped cream canister on top. Garnish with one piece of oyster leaf, a celery leaf and a few strands of crispy vermicelli.

 

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