Fruit-Filled Hamantaschen

In a large mixing bowl, cream butter and sugar together until smooth and creamy. Beat in the eggs one at a time. Add orange juice and vanilla, stirring to fully incorporate. Mix in the baking powder; gradually stir in the flour, mixing until the dough forms a ball. Cover with plastic wrap and refrigerate for at least 2 hours or overnight.

Position oven rack in in the upper third of the oven. Preheat oven to 375º F. Line cookie sheets with cooking parchment paper.

On a lightly floured work surface, roll the dough out to 1/4-inch thickness. Using a cookie cutter or glass, cut the dough into 3-inch rounds. Transfer rounds to prepared cookie sheets.

In a small bowl, mix egg, water and sugar together to make egg glaze. Brush each dough round with the egg glaze. Spoon 1 teaspoon of fruit preserves in the center of each round. Pinch 3 sides of each round together, creating a triangle. Brush the cookies with additional egg glaze.