Preheat oven to fan forced 190°C and butter a 23cm loose bottomed flan tin. Set aside.
Place sugar into Thermo bowl and mill 10 sec/speed 10.
Add flour and butter and mix *6-7 sec/speed 8.
Add vanilla bean paste and yolks and mix 6-7 sec/speed 6 or until pastry forms soft balls.
Tip out onto floured Silpat mat and bring together with hands into large disc shape. Roll out using floured rolling pin and line prepared flan tin. Place in freezer for at least 15 minutes. Remove, line with baking paper and weights (rice, beans or proper pie weights) and bake for 15-20 minutes. Remove weights and bake a further 5 minutes until pastry is no longer shiny. Remove and cool slightly before filling with prepared filling.
Place cacao chunks into Thermo bowl and mill 10 sec/speed 8 until powdered.
Add butter, sugar, and maple syrup to Thermo bowl and melt 6 min/50℃/speed 1.
Add eggs through hole in lid and beat 30 sec/speed 8. Scrape down sides of bowl if necessary and repeat. You will have a thick mousse like consistency.
Place pecans into prepared pastry case, scrape filling on top and spread with spatula. Bake a further 10-15 minutes until set in centre. Chill completely before serving with lashings of cream...kind of necessary due to the dense nature of pure cacao. Of course if you can't source the pure cacao in block form, you can use 85% dark chocolate, for less of a hit, use 70% and maybe adjust the sugar to taste…you may still need it unless you are a total chocoholic!