Place the yolks, cinnamon, hazelnut powder, baking powder, sugar and flour in a food processor.
Add the cold butter cut into pieces and the rum (if you wish to use it).
Mix with the "k" until the dough is homogeneous, no more!
Spread on a sheet of parchment paper to a thickness of 2mm. The dough will only rise a little, as there are no whites and just a touch of baking powder.
Line a circle, square or pie pan with the shape of your choice.
My students in the "tartlet" classes have become pros and this recipe will be no problem for them!
Pour the chosen jam on the pastry base. It is better to use a "home-made" jam low in sugar, or a light commercial one. With a normal jam, the result may be too sweet.
Spread evenly.
With the remaining dough, cut strips or stars to make this Christmas Linzertorte!
Place the stars on the jam.
Bake for 50 minutes at 175°C. The jam will boil. The dough should be well cooked and golden brown!
Place on a wire rack and carefully remove from the pan.
To make a more classic Linzertorte, simply roll out another circle (there is enough dough to make two), then cut strips with a rolling pin. Arrange them on the pastry filled with jam (here raspberries).Then from pass the roller over the circle to cut the dough. Cook in the same way, watching the cooking time, to be adapted according to the size of the Linzertorte.
Carefully unpack as the Linzertorte is very crumbly!