Mix all purpose flour, fine sugar, salt and unsalted butter together. Add egg yolk and continue to mix until well
Grease mould with butter and align dough into mould.
Poke the dough with a fork. Bake at 170c for 10 minutes.
Melt dark chocolate, butter and vegetable oil on low heat.
In another bowl, whisk 2 eggs and fine sugar.
Then add chocolate mixture and continue to mix.
Add flour, cocoa powder and salt and mix well.
Pour mixture into the tart shell and add chocolate chips as toppings. Bake at 180c for 20-25 minutes.