Pre-heat the oven to 180'C.
Whisk the egg whites and the caster sugar until you obtain stiff, glossy peaks. For best results, please ensure that your mixing bowl is absolutely pristine before whisking the egg whites.
Use a food processor to grind the hazelnuts, if necessary. Run a whisk through the ground hazelnuts to break up any lumps, then fold them through the egg whites in three batches.
When the mix is thoroughly combined, place in a piping bag. Pipe out three evenly sized layers of the dacquoise batter on baking sheets lined with baking paper. Each layer should be about 1cm thick in order to bake evenly.
Place in the oven, and bake for about 15 minutes, or until the biscuit feels crisp and dry to the touch. Set aside or keep in an airtight container until needed.
Toast the whole hazelnuts until they just begin to turn golden. Leave to cool down completely before roughly crushing.
In a clean pan, heat 175g of caster sugar and 75ml of water until you obtain a pale amber caramel. If you have a sugar thermometer, the caramel should be about 175'C.
Remove the pan from the heat and leave the caramel to rest for 2-3 minutes, before using a spoon to drizzle the caramel onto a paper-lined baking sheet. Before the caramel cools down completely, sprinkle with the chopped hazelnut. Leave to set away from moisture until needed.
Chop the milk chocolate,if necessary. Bring 150ml of double cream up to the boil, and pour over the milk chocolate. Let this sit for 2 minutes before stirring until smooth. Set aside and leave to cool down to room temperature.
Whip the remaining 100ml of double cream to a soft peak, keep refrigerated until needed.
When the ganache has cooled down sufficiently, beat with a spatula to loosen, if necessary. Fold in the softly whipped cream in two stages. Stir in the smoked Maldon salt, if using. Pour into a piping bag, and use immediately.
Pipe the chocolate whipped cream onto two layers of dacquoise. Stack the two filled layers, and finish with a third one on top.
Keep chilled until ready to serve.
«The ground hazelnuts are traditional for a dacquoise base,but can be substituted with any nut of your choice, such as ground almonds or even dessicated coconut.»