Sift flour and cocoa powder together; set aside. In a food processor, cream butter, salt and sugar. Add the egg and powders in 2 times. Mix until combined and chill for a couple of hours (can be made in advance). Flour countertop, work out half of the pastry – make it supple but still cool, and roll dough out into a 3mm (0.12”) disk and lightly prick. Make a 8” (21cm) greased round pan, tart ring or make individual if desired. This recipe can handle 3 tart shells. The dough can be stored a week in the refrigerator or kept frozen for up to 6 months. Better leave the tart shell to rest overnight in the refrigerator to dry out; uncovered. Blend bake tart shell for 20 minutes at 350ºF/180ºC. Remove pie weights and bake for 10 min more; cool.
*To make peanut buter from scratch, look up at Peanut Spread Recipe. Combine peanut butter and melted milk chocolate. Add corn flakes, nuts and chocolate pearls. Spread evenly in the baked tart shell; set aside.
*To make Gianduja from scratch, look up at Crunchy Chocolate Candy Recipe. Blend all ingredients together. Pour over the nut-chocolate crunch and leave to set in a cool area or refrigerator. Make another layer of ganache if desired using a smaller in diameter ring lined with acetate or parchment; freeze to harden and unmold. Top the tart with and thaw completely before slicing the tart.
Mix 10g sugar with pectin; set aside. Heat up a small pan and make a light brown caramel a sec (dry caramel) with remaining sugar. Stir in butter and add the sugar-pectin or lemon juice and cocoa nibs. Spread hot mixture evenly inside a pastry ring (same size as the top ganache). Bake at 400ºF/200ºC for 10 min max. Remove tart ring and cut into 8 triangles while still warm. Let cool. Slice tart and top each with a cocoa nibs tuile. Enjoy!