HAMANTASCHEN: Stuffed Purim Cookies with Prune Butter

GENERAL INGREDIENTS:
Sweet, unsalted butter or vegan/non-dairy style butter (such as Earth Balance)
Sugar
Egg
Almond or vanilla extract
Salt
All-purpose flour

For Filling and Decorating:
Prune butter, apricot butter, fig butter (or mix of all 3)
White and/or milk/dark chocolate chips (optional; for melting and dipping; if available, mini chips melt better)
Sprinkles or decorative sugar (optional; need melted chocolate for it to stick)

EQUIPMENT:
Measuring cups and spoons
2½-inch round cookie cutter or drinking glass
2 half-sheet baking trays or large cookie sheets
Parchment paper, for lining the pans and forming the dough
Plastic wrap or baggy, for wrapping the dough
Large mixing bowl and spoon, for mixing the dough ingredients
Small bowl of cold water, for pinching the dough together to form triangles