I make this all the time – its really kick ass. I read it in a Pierre Herme cookbook a while back, but have modified the process to be a little safer – less likely to overcook. His recipe calls for you to flash the tart for 11 minutes in a hot oven, but there is too much room for error here. I’ve lowered the temp to 325 and added a couple of minutes to the final bake time. I also add nutella to the chocolate layer which makes it extra lovely.



CRUST:
285 g butter
150 g confectioner’s sugar
100 g finely ground blanched hazelnuts
1/2 tsp salt
1/2 tsp vanilla extract
2 large eggs
490 g flour

Method
Set oven on 375 or 350 convection

Cream butter. Add sugar, hazelnuts salt and vanilla extract. Slowly mix in the eggs and continue mixing until smooth. Add the flour and mix to combine, should be no more than a minute. chill in fridge for 1 hour.

Remove from Fridge. Flatten dough, push it into a tart pan, and cover the base with parchment and pastry weights (I use dried cannelli beans). Bake for 20 minutes or until half cooked.

FILLING Layer 1:
200g Nutella

FILLING Layer 2:
150g bittersweet or semisweet chocolate
200g unsalted butter
5 egg yolks
50 g sugar
150g chopped hazelnuts
100 g nutella

METHOD:
Drop oven to 325 convection.

While the crust is cooling, spread the 200g of nutella (use what you need) to cover the bottom of the crust. Let cool.

Meanwhile, melt the chocolate and butter over a double boiler. mix together using a rubber spoon until smooth and incorporated. Add the vanilla, sugar and eggs in batches, mixing carefully to combine but not whip. Fold in the 100g of nutells. Pour into the tart shells and let cool slightly.

Bake at 325 convection for 10-12 minutes until the top is dull. If you start to see bubbles form on top, remove the tart from the oven immediately. Serve cool, not cold.