For the Linzer hearts, sift the flour and powdered sugar onto a pasta board, add the vanilla sugar and spread the butter in pieces on top.
Make a well and add the egg yolk and knead everything into a smooth dough, adding a little milk if needed. Then let the dough rest in the refrigerator for 1 hour.
Then roll out the dough thinly and cut out hearts once with a heart hole and once without a hole. Place them on a baking tray and bake at 180 degrees.
After cooling, sprinkle each heart with a hole with powdered sugar and put together with a heart without a hole.