In a bowl, put the sifted flour, sugar and cooled and sliced butter.
With your hands, bring it to the state of crumbs.
Add the egg, cold water, knead the dough.
Assemble the dough into a ball.
Roll out the dough into a thin layer 3 mm thick.
For the filling, mix cane sugar, black currant, starch. Mix it.
Put the dough layer on a greased round shape, put the filling in the center, leaving the edges free.
Roll the edges of the cookies on the cake.
Whisk the yolk, spread it on the cake.
Bake the galette in a preheated 180 degree oven for 35 minutes.
