This Austrian classic began its long history as a lattice-topped, jam-filled Linzer Torte, which some claim as the oldest tart in the world. The citizens of Linz clearly couldn’t get enough of jam-filled treats, though, and also created these sandwich cookies that have become just as popular. Try this red currant jelly-filled sandwich cookie with its crumbly pastry of almonds, cinnamon and lemon peel, and we think you’ll understand why this treat remains as popular as ever!