Sift the dry ingredients (flour and salt) into a mixing bowl.

Cut the butter into small pieces and mix it into the dry ingredients using a scraper.

Add egg yolks and knead the mixture into a dough.

Wrap the dough in plastic wrap and refrigerate for 1 hour.

Roll out the dough to a suitable thickness and cut into circles using a cookie cutter. Use a smaller cutter to create a hole in half of the circles.

Place blueberry jam on the whole circles and cover with the holed circles.

Brush the cookies with egg wash for a golden finish.