For the blueberry hearts, knead a shortcrust pastry from all ingredients except jam and chill for about 2 hours. Then roll out the dough 3 – 4 mm thick and cut out round slices.
Half of the slices get a heart cut out in the middle. Bake each tray separately at 180 degrees top/bottom heat on second lowest rack for 8 – 12 minutes.
Stick cooled cookies together with blueberry jam.