Preheat your oven to 350°F (180°C) and prepare a 9x13 inch cake pan by greasing and flouring it.

In a medium bowl, sift together the cake flour, baking powder, baking soda, and salt. In another bowl, mix the buttermilk with freshly squeezed lemon juice and set aside.

In a large mixing bowl, cream together the softened butter, granulated sugar, and lemon zest until fluffy (about 2-3 minutes).

Add the vanilla extract, incorporating each egg one at a time while scraping down the bowl as needed.

Begin incorporating the dry ingredients by mixing approximately one-third of the flour mixture into the butter mixture, followed by half of the milk and lemon juice mixture. Repeat, ending with the flour. Avoid overmixing.

Toss the fresh blueberries with the two teaspoons of flour before gently folding them into the cake batter.

Pour the batter into the prepared pan and bake for 30-35 minutes, or until a toothpick inserted in the center comes out clean.

Allow the cake to cool fully in the pan.

For the frosting, beat cream cheese and butter until smooth.

Add lemon juice, then gradually mix in powdered sugar to achieve desired sweetness and consistency, adding whipping cream as needed.

Frost the cool cake with the cream cheese frosting as desired.