1. Preheat your oven to 180°C/160°C/gas mark 4 and grease and line a regular brownie tin.
2. In the bowl of your stand mixer, cream together your butter and sugar until light, fluffy and pale in colour.
3. Add the eggs, flour and lemon zest and mix together until just combined, being careful not to over-beat the mixture.
4. Stir through the blueberries.
5. Spoon the mixture into the tin and use a spatula to spread it out evenly.
6. Bake your traybake in the oven for 45-50 mins, until a thin skewer inserted into the centre of the cake comes out clean.
7. Once the cake is baked, remove it from the oven and allow it to cool in the tin until room temperature.
8. To make the buttercream topping, begin by creaming the butter in the bowl of a stand mixer until pale and smooth. This may take a while, but the longer you leave it, the better.
9. Sieve in the icing sugar and pour over the lemon juice, before mixing until just combined. Set aside until ready to use.
10. When you are ready to assemble your traybake, begin by transferring the cake onto a large plate or cake board.
11. Give the buttercream a final mix, before adding to the top of the cake and spreading out evenly with an offset spatula.
12. Decorate the cake with the rest of the blueberries and slice into small square shaped portions to serve.
Is there anything better than a slice of lemon cake? What about a lemon cake, stuffed full of fresh blueberries and topped with a subtle lemon buttercream and even MORE blueberries? Obviously, you’ll need to give it a try and find out for yourselves, but we think you’re going to love it!