Put cornstarch, butter, flour, orange zest, baking powder, sugar and juice and egg yolks in a suitable bowl and prepare a smooth dough.
Place in the refrigerator for 30 minutes. Preheat oven to 180 degrees… Form the dough into a roll, which is then cut into slices. Place the dough slices on the baking sheet and bake for about 15 min. until light yellow. Cool. Press two cookies at a time with the orange marmalade. Dust with powdered sugar, vanilla sugar or cocoa.