Preheat your oven to 350°F (175°C). Grease your bundt pan thoroughly with butter or a non-stick spray.
Cream together the unsalted butter and sugar using an electric mixer until light and fluffy, about 3-5 minutes.
Add the eggs one at a time, mixing well after each addition. Stir in the vanilla essence.
Mix in the buttermilk, zest, and juice of the lemons. The mixture may look slightly curdled.
In a separate bowl, whisk together the white flour, baking powder, and salt.
Gradually add the dry ingredients to the wet mixture, folding gently with a rubber spatula.
Toss the blueberries with flour to coat them. This will help prevent them from sinking.
Gently fold the floured blueberries into the batter.
Pour the batter into the prepared bundt pan, smoothing the top with a spatula.
Bake for 45-50 minutes, or until a toothpick inserted in the center comes out clean.
Let the cake cool in the pan for about 10 minutes, then invert it onto a cooling rack to cool completely.
Beat together the cream cheese and butter until smooth. Gradually add the powdered sugar and vanilla essence, mixing until creamy.
Once the cake is cooled, spread the cream cheese frosting over the top.
Finish with a sprinkle of lemon zest on top for decoration.
