Preheat the oven to 170°C, gas mark 3. Line a loaf tin with baking parchment.
Whisk all the ingredients together in a large bowl until fully incorporated and it is pale and creamy
Pour into the tin and bake for 55-65 minutes spring and cooked through. Cool the cake slightly then remove from the tin and place on cooling rack to cool completely.
For the icing – simply mix enough lime juice into the icing sugar until you have a thick pouring consistency – drizzle over the cake using a spoon or piping bag and finish with strands of lime zest.