Preheat oven to 180 C (160 c fan). Grease and flour a cake tin or line with paper case. Sieve flour, baking powder, bicarbonate of soda and salt together and set aside.
Cream butter and sugar with electronic hand mixture in a mixing bowl until light and fluffy.
Add the eggs one at the time and continue beat it until it smooth. Add the lemon juice and lemon zest. Add the flour mixture and mix well.
In a small saucepan, heat up blueberries, icing sugar until sugar dissolved. Turn the heat of and leave it to cook down.
Pour the cake mixture into the cake tin up until half way through then add some blueberry jam in. Use a fork or bbq skewer to swirl the blueberry jam around the top up with the rest of the cake mixture.
Bake for 50-60 minutes. You can test if your cake cooked through by put a wooden skewer right in the middle of the cake and if they cooked the wooden skewer will come out dry.
Make a glaze, mixing icing sugar with lemon juice. You will have to check your icing mixture as it needs to be a very think consistency. If it’s too runny you can add some more icing sugar in.
When the cake is totally cool, drizzle the lemon icing over it and sprinkle some lemon zest on top.
