Preheat oven to 180C and place an oven rack on a lower-middle shelf. Grease and line a 20cm cake tin. (We love Wilton’s anodised tins for this type of cake as they give a light, blonde, tender crust – and we always recommend Wilton cake release for effortless, stress free unmoulding). Whisk sugar, baking soda, baking powder and salt together in a medium bowl for one minute. Don’t be tempted to skip this step – immaculate incorporation of your dry ingredients is key in a cake as simple as this.
Add the lemon zest, olive oil, buttermilk, egg and orange blossom water and whisk vigorously until batter is smooth and well emulsified. Sift in the flour and, again, whisk until well combined. Turn into prepared pan and bake until the cake is firm but your finger still leaves an impression in the surface (about 30 minutes). A cake tester should come out clean (ish) but still moist.
Cool for about 10 minutes before loosening the edges with a palate knife and turning the cake out to cool on a wire rack. Serve warm or at room temperature with your choice of accompaniments (or as it is, it’s always good). This cake keeps well when stored in an airtight container (3-4 days).