Preheat oven to 180ºC and line a 2lb loaf tin with baking paper.

Place the softened butter and the caster sugar in a bowl and beat with an electric hand whisk for about 2 minutes until the butter is pale yellow and the mixture is fluffy.

Once the butter and sugar mixture is light and fluffy add in the lemon zest and 1 tablespoon of the lemon juice and the eggs. Add in the eggs all at once and whisk. The mixture may look split. This is perfectly normal and will come back together when the flour is added.

Soft in the flour and ground almonds. Now switch to a wooden spoon or a spatula and gently fold in 150g the blueberries reserving the rest. Bake in the preheated oven for about 15 minutes, then gently scatter the top of the cake with the remaining blueberries and continue to bake for a further 15 minutes, until the cake is golden. Cover it with some foil and continue to bake for a further 20 minutes until a toothpick or knife comes out with only a few moist crumbs.Remove from the oven and let cool on a wire rack in the tin for 15 minutes, before turning out of the tin and allowing to cool completely.

Making the glaze-

Make the glaze by mixing the icing sugar with the lemon juice in a small bowl, until the sugar has dissolved and the glaze has a runny consistency. Use a spoon to drizzle the glaze over the cake and leave to set for a few minutes before slicing.