In a bowl of a stand mixer fitted with a paddle attachment, add butter, flour, sugar, salt and almond flour and beat until the mixture resembles breadcrumbs.
Add the egg and bring the mix together until it forms a ball.
Roll dough to 2.5 mm/ 0.10 inches thickness between two parchment paper, cover in cling film, and refrigerate at least for two hours.
Using a 4-inch/10 cm round cutter, cut rounds of dough and place on a perforated baking sheet or forosil pavoni.
Cover the round sable with another forosil ( perforated baking mat).
Bake sable until fully baked through, 15-20 minutes. Let cool to room temperature.
Pipe dulcey ganache over half of the sable. Cover the filling with a second matching sable.
How to Make Valrhona Dulcey Ganache:
Bring heavy cream and inverted sugar to a boil in a small pot.
Pour over chocolate and whisk to emulsify.
Cool to 35 °C/95 °F before adding butter and processing with a hand blender until smooth.
Let the ganache set to 23 °C/73 °F and transfer to a pastry bag.