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 together until light and fluffy, approximately 3-4 minutes.
03 - Add the eggs one at a time, mixing thoroughly after each addition until fully combined.
04 - Stir in the Greek yogurt, lemon zest, and rosewater until the mixture is uniform.
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 until just incorporated, being careful not to overmix.
07 - Pour the batter into the prepared cake tin, using a spatula to smooth and level the top evenly.
08 - Bake for 40-45 minutes, or until a wooden skewer inserted into the center comes out clean and the top is golden brown.
09 - Allow the cake to cool in the tin for 10 minutes, then carefully transfer to a wire rack to cool completely.
10 - In a small bowl, whisk the icing sugar with rosewater, adding liquid gradually until a thick but pourable consistency is achieved.
11 - Drizzle the rosewater icing over the completely cooled cake, then immediately sprinkle with chopped pistachios and dried rose petals.