Preheat the oven to 190°C, fan 170°C, gas 5. Line a 33x23cm Swiss roll tin with baking parchment.
Using an electric hand mixer, beat the eggs and sugar together for about 5 minutes until the mixture is very pale in colour and the whisks leave a trail. Fold in the lemon zest and 1 tablespoon of warm water, then sift in the flour, a third at a time, folding gently into the egg mixture using a large spoon.
Pour the mixture into the prepared tin, spread it evenly and bake in the oven for 10-12 minutes, or until the centre springs back when touched.
Meanwhile, place a piece of baking parchment on the work surface and sprinkle liberally with sugar. Take the sponge out of the oven and invert it onto the sugared paper. Remove the tin and carefully peel away the baking parchment tin liner. Trim the edges. Score 1cm in from the edge all the way along one of the shortest sides, so the sponge tucks inwards easily. Roll up the sponge with the sugared paper inside, then leave to cool.
Once cold, unroll and spread with the lemon curd. Roll up the sponge into a swiss roll shape (use the sugared paper to help you). Sprinkle with the almonds.