For the Linzer cake, knead a dough from all the ingredients (except the baking wafers, which are not). Set aside 1/4 of the dough for the typical lattice.
Roll out the remaining dough into a base for a 28 cm springform pan and place in the greased pan. Cut baking sheets and place them on the dough, leaving a 1 cm border.
Mix the dough for the lattice with some more rum until smoother, put it in a piping bag and first pipe a border on the cake.
Then spread the jam on the baking wafers and pipe the lattice. Bake the Linzer cake at 180 degrees for about 35 minutes.