01 - Preheat oven to 340°F (170°C). Grease and line an 8-inch round cake pan with parchment.
02 - In a large mixing bowl, beat softened butter and caster sugar until pale and fluffy using an electric or hand whisk.
03 - Incorporate eggs one at a time, blending well after each addition for a smooth mixture.
04 - Mix in Greek yogurt, lemon zest, and rosewater until just blended.
05 - In a separate bowl, whisk together ground almonds, all-purpose flour, ground cardamom, baking powder, and salt.
06 - Gently fold dry mixture into the wet base using a spatula, mixing until just incorporated. Do not overmix.
07 - Pour batter into prepared pan and smooth the surface evenly.
08 - Bake for 40–45 minutes or until a toothpick inserted in the center emerges clean.
09 - Allow cake to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
10 - In a small bowl, mix confectioners' sugar with enough rosewater to create a thick but pourable icing.
11 - Drizzle icing over the cooled cake, then sprinkle with chopped pistachios and dried rose petals if desired.