The flavors in this bar were inspired by linzertorte, a classic European dessert originating in Linz, Austria.
Make these fabulous bars ahead of time. Line your pan with aluminum foil, leaving the edge of the foil above the rim of the pan on two opposite sides; grease foil in bottom of pan lightly. Bake bars as directed. When cool, use foil "handles" to remove the whole square from the pan. Wrap airtight and freeze. Before serving, unwrap and let stand about one hour until room temperature.
Apricot lovers can use apricot preserves instead of raspberry and ground almonds instead of the walnuts for variety with this delicious recipe.