Cooking the mackerel with a blow-torch gives a lovely charred flavour without overcooking the flesh.
To make the blini, mix the yeast, sugar, milk, flours and egg yolk together in a bowl to make a paste.
Whisk the egg whites in a separate bowl until they form stiff peaks, then fold them into the yeast mixture. Cover the bowl and set aside at room temperature for 20 minutes.
Heat a frying pan until medium hot, add a little vegetable oil and small spoonfuls of the blini mixture.
Cook the blini on each side until golden-brown then remove and drain onto kitchen paper. Repeat with the remaining batter and keep the blini warm until ready to serve.
For the beetroot, place the redcurrant jelly, vinegar and cloves into a saucepan and cook until reduced down to a glaze thick enough to coat the back of a spoon.
Pass the mixture through a sieve into a clean bowl, whisk in the mustard then fold the beetroot into the pickle mix and keep warm.
Whisk the crème fraîche until thickened, add the chives and season with salt and freshly ground black pepper.
Cut the mackerel fillets in half lengthways. Drizzle with rapeseed oil, gently blow torch on both sides until cooked through then season with salt and freshly ground black pepper.
To serve, place the mackerel onto the serving plates with a little of the chopped shallots, the warm beetroot pickle, blini, crème fraîche and some Avruga caviar.
