Put the sugar and butter in a large mixing bowl and whisk together until pale.
Add the eggs one by one, whisking as you go.
Add the lemon zest and juice and whisk again
Sift in the flour then fold together.
Put a couple of large spoonfuls of batter into the base of each prepared tin - this creates a cushion for the blueberries to discourage them from sinking. Level off.
Toss the blueberries in 2 tbsp flour.
Fold the blueberries into the cake batter.
Spoon the batter into the lined tins, sharing evenly and level off.
Put the tins into the oven, ideally on the same shelf, and bake for approximately 1 hour or until a finger pressed lightly on top springs back and a skewer pushed into the centre of the cakes comes out clean.
Leave to cool in the tin until safe to touch, then release onto a wire rack to cool completely.
Make the cream cheese frosting
Put the softened butter in a bowl and whisk until pale and creamy.
Sift in the icing sugar, add the vanilla extract and whisk until very pale, creamy and increased in volume.
Add the chilled cream cheese and fold through gently. Don't overwork it as it will loosen. If it looks like it’s starting to loosen, pop in the fridge for 10 minutes to firm up.
Assemble the cake
Put the first cake on a board and pile about one third of the frosting on top and spread to the edges.
Place the second cake on top and pile another third of the frosting on top.
Use the remaining frosting to neatly frost the sides.
Finely grate the lemon zest over the top of the cake
Place the whole cake in the fridge for 1 hour to firm up before slicing and serving.