For the Cured Salmon, combine the sparkling wine, salt and lemon zest in a wide bowl and stir to combine.
Cut the salmon fillet lengthways to separate the thinner belly side from the thick side of the fillet. Trim the thick part of the salmon fillet to get a neat barrel shape. Reserve the belly side and all trimmings for the Salmon Tartare.
Slice the thick, barrel shaped salmon portion into 5mm slices and place into curing mixture, ensuring salmon is fully submerged. Cover the bowl with cling film and set aside in fridge to cure for 1 hour.
For the Salmon Tartare, trim the reserved salmon belly and trimmings of visible fat and sinew. Cut the belly into a 5mm dice and place into a small bowl. Add the diced avocado and toss gently to combine, being careful not to break up the avocado. Cover the bowl with cling film and set aside in the fridge until ready to dress.
For the Sweet Pea Dumpling, make the dumpling dough by placing flour, eggs, oil and salt into a food processor. Pulse until dough starts to form, adding a little water if required to bring the dough together.
Transfer the dough to a lightly floured work surface and knead for 5 minutes until smooth and pliable. Wrap the dough in cling film and set aside in the fridge to rest for 30 minutes.
Meanwhile, place peas, butter and cream into a microwave safe bowl and microwave on high for 1 ½ minutes, until peas are bright green and just tender. Remove from microwave and roughly mash peas. Season to taste and set aside to cool until needed.
Bring a large saucepan of lightly salted water to the boil.
Remove dumpling dough from the fridge and pass through a pasta machine, in batches, working down to the thinnest setting. Lay lengths of dough along a lightly floured bench. Use and 8cm ring cutter to cut 8 rounds from dough.
Spoon the cooled pea filling into centre of the dumpling rounds. Run a finger dipped in water round the edges of the dumpling rounds to moisten, then fold each dumpling round in half with the seam meeting on the top of the dumpling. Press edges together to seal.
Cook dumplings, in batches, in the boiling water until dough is tender and filling is hot, about 3 minutes. Remove dumplings from water, drain on kitchen paper and set aside, keeping warm until needed.
For the Avocado Mousse, combine all ingredients, except salt and pepper, in the bowl of a small food processor and blitz until light and smooth. Season to taste with salt and pepper. Transfer mix to a piping bag and set aside in the fridge until needed.
For the Lemon Curd, place all ingredients in a medium sized, microwave safe bowl. Whisk to combine well. Place the bowl in the microwave and cook in 30 second bursts, whisking well at each interval, until curd has thickened, about 3 minutes in total. Transfer curd to a piping bag and set curd aside to cool until needed.
To serve, dress the Salmon Tartare with lemon zest, lemon juice and salt to taste and toss gently to coat. Drain the Cured Salmon and pat dry with kitchen paper.
Place 2 spoonfuls of the Salmon Tartare, about 5cm apart, onto each serving plate. Add 2 pieces of Cured Salmon to each plate, standing on its side near the tartare. Place 2 dumplings next to the salmon on each plate. Pipe small dots of Avocado Mousse and Lemon Curd around the Salmon Tartare and finish with a few fresh peas and asparagus tips scattered over the dish. Spoon a few shavings of crushed ice over the Salmon Tartare. Serve immediately.