Pre-heat the oven to 170C/gas mark 3. Grease and line a swiss roll tray. Sift the flour, ground almonds, baking powder and ground cardamom into a large mixing bowl and stir in the sugar.
In another bowl, beat the eggs lightly. Add the yogurt, oil and orange zest to the eggs, then add the mixture to the dry ingredients. Pour the batter into the lined tray and bake for 30-35 minutes or until golden.
Put the sugar, orange juice and rose water in a small saucepan and bring to a gentle boil. Reduce a little, then brush it over the cake and let it cool down. Cut the cake into 24 squares, and sprinkle with the pistachio and rose petals.