In the bowl of a stand mixer fitted with paddle attachment, mix butter with sifted icing sugar.
Add lightly beaten whole egg and mix to combine.
Add the sifted flour, cocoa, hazelnuts meal with salt and mix just to combine.
Flatten the dough into a round disc, wrap in cling film and refrigerate for 8 hours.
Brush the interior of your ring with butter (7.5 inches - 19 cm.) and place on a baking tray with baking paper (I used micro perforated round tart ring, micro perforated tray and Silpat non-stick mat).
Roll the dough gently until you have an even 3mm thickness.
Gently ease the dough into the sides of the ring, use your fingertips to press the pastry into the edges and up the wall of the tin.
Using the knife, remove the overhanging pastry.
Prick the base with a fork and refrigerate for 2 hours.
Heat fan oven at 320 F - 160°C.
Bake the tart shell for 20 minutes and let cool a few minutes.
Let completely cool and remove the ring.
Set aside to assemble.
Melt chocolate, add praline paste and stir to combine.
Add shredded Gavottes® or corn flakes and combine.
Spread a thin layer in the tart shell and let the chocolate set, room temperature or in the fridge.
Heat on a medium heat the milk with inverted sugar, until you reach 170F - 70°C.
Add hot milk in 3 batches, over the chocolate, mixing with a spatula, until you get a smooth and shiny mixture.
When the ganache reaches 95F - 35°C, add the butter and mix to combine.
Pour the ganache in the tart shell and refrigerate until set.
Place hazelnuts, almonds and icing sugar in a sauce pan.
Cook on a medium heat, stirring constantly, until sugar is completely melted and completely wraps hazelnuts and almonds.
Add cocoa butter, mix to combine, spread on baking paper and immediately separate nuts using 2 forks so that each stands alone on sheet.
Just before serving, sprinkle a generous layer of candied nuts over the ganache.
Serve and enjoy.