1. Prepare the Crust:

1. Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
2. In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time, then stir in the lemon zest.
3. In another bowl, whisk together the flour, baking powder, and salt. Gradually add the dry mixture to the wet ingredients, mixing until combined. Stir in the pistachios.
4. Roll dough into small balls, place on the prepared baking sheet, and press a hidden pistachio heart into each cookie before covering it with dough.
5. Bake for 12 minutes or until the edges are lightly golden. Cool on the baking sheet before transferring to a wire rack.