Similar to a strudel, a jalousie is made of pâte feuilletée and can have apples, nuts, frangipane, jam or other ingredients folded inside.
What makes it a jalousie is the pastry lattice work on top, resembling a jalousie (or louvred) window, or Venetian blinds—the kind you can see out of without being seen, ideal for jealous snooping.
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