Place the flour, milk, eggs and a pinch of sea salt in a bowl, then whisk to a smooth batter.
Heat 1 teaspoon of oil in a small non-stick frying pan over a medium heat, then wipe around and away with a ball of kitchen paper.
Once hot, add a ladleful of batter, tilting the pan to spread, then cook for 2 to 3 minutes each side, or until lightly golden. Remove to a plate, and repeat until you’ve used all the batter.
Smash up the chocolate and place in a heatproof bowl with the butter and a pinch of sea salt. Pop the bowl over a pan of gently simmering water (don’t let the bowl touch the water), and stir occasionally until melted. Remove from the heat.
Toast the nuts in a dry frying pan for 2 to 3 minutes, or until golden then bash in a pestle and mortar until fine.
Stir 200ml of the cream and a handful of bashed nuts through the melted chocolate.
Whisk the remaining cream with the vanilla extract and sugar until thick.
To build your cake, spread a blob of cream over a serving plate or board, pop a pancake on top and press gently. Spread some chocolate over the pancake and top with another pancake. Keep doing this, alternating between cream and chocolate, until you’ve used all the pancakes, remembering to keep some cream back for the top.
Smooth the sides with a spatula or palette knife to tidy up the edges, then pour the remaining cream on top, letting it drip down the sides to spread to cover the cake.
Press the remaining nuts around the sides, then scrape over a few gratings of dark chocolate. Decorate the base with some lovely fresh berries, if you like, then serve.