01 -
Blend raspberries in a blender or food processor until smooth. Push puree through a metal sifter to remove seeds, if desired. Heat the seedless puree in a saucepan over low-medium heat until thickened and reduced to about 1/4–1/3 cup, approximately 15-20 minutes. Cool completely.
02 -
Preheat oven to 325°F (160°C) and line a 9x13 inch (23x33 cm) baking pan with parchment paper, leaving an overhang. Mix flour, sugar, cornstarch, and salt in a bowl. Stir in melted butter to form a thick dough. Press into prepared pan, creating a slight lip around edges. Bake for 20-25 minutes until the top is set and slightly golden. Remove from oven and gently prick the surface with a fork without penetrating to the bottom.
03 -
Whisk sugar and cornstarch in a large bowl to remove lumps. Add eggs and whisk until smooth. Mix in cooled reduced raspberry puree and lemon juice. The mixture will be liquid. Pour over the baked shortbread base.
04 -
Bake at 325°F (160°C) for 20-25 minutes, or until the top is set. Allow to cool in the pan for at least 1 hour at room temperature, then refrigerate for at least 2 hours.
05 -
Use parchment paper overhang to lift the bars out of the pan. Slice with a sharp knife, wiping clean between cuts. Store bars in an airtight container in the refrigerator for up to 5 days.