Make the Dough

In a large bowl, combine flour, baking powder, sugar, and salt.

Add eggs, Crisco, vanilla, and the orange and lemon zest and juice.

Knead gently, adding a little extra flour only if needed, until the dough becomes soft and smooth.

Divide dough into large grapefruit-sized balls.

Chill dough for at least 1 hour.

Make the Prune Lekvar Filling

Add prunes, water, orange juice, and orange zest to a saucepan.

Simmer until prunes soften and the liquid reduces and thickens.

Add brown sugar and optional lemon juice; continue cooking until thick and jam-like.

Mash with a fork or puree with an immersion blender.

Stir in chopped nuts if desired.

Let cool completely before using.

Shape the Hamantaschen

Preheat oven to 360°F.

Roll chilled dough very thin — about ⅛ inch thick.

Cut circles using a juice glass or wine glass.

Place a small spoonful of prune filling in the center of each round.

Fold into a triangle and pinch tightly closed on all three corners.

Bake

Transfer cookies to a parchment-lined baking sheet.

Bake at 360°F for 15 minutes, or until lightly golden at the edges.

Cool completely before storing.