01 - Preheat the oven to 340°F. Butter and line an 8-inch round cake tin with parchment paper.
02 - In a large bowl, beat the softened butter and caster sugar with an electric mixer until pale, light, and fluffy.
03 - Add the eggs one at a time, mixing thoroughly after each addition until fully blended.
04 - Fold in the Greek yogurt, lemon zest, and rosewater until evenly combined.
05 - In a separate bowl, whisk together ground almonds, flour, cardamom, baking powder, and salt.
06 - Gently fold the dry ingredients into the wet mixture using a spatula, mixing until just incorporated. Do not overmix.
07 - Transfer batter to the prepared tin, smooth the surface, and bake for 40-45 minutes until a skewer inserted in the center comes out clean.
08 - Let the cake rest in the tin for 10 minutes, then remove and transfer to a wire rack to cool completely before icing.
09 - Whisk icing sugar with rosewater in a small bowl, adding liquid gradually until achieving a thick but pourable consistency.
10 - Drizzle the icing evenly over the cooled cake, then immediately sprinkle with chopped pistachios and dried rose petals.