Preheat your oven to 350°F (175°C). Grease a 9x13 inch baking dish and line the bottom with parchment paper.

In a medium bowl, whisk together 2 cups of all-purpose flour, 1 tablespoon of baking powder, ½ teaspoon of baking soda, and ½ teaspoon of salt.

Beat together ¾ cup of softened butter and 1 ½ cups of granulated sugar on medium speed until light and fluffy, about 2-3 minutes.

Add 3 large eggs, ½ cup of buttermilk, and 2 teaspoons of vanilla extract to the butter mixture and mix on low until just combined.

Gradually add the dry ingredients to the wet mixture, mixing until just combined.

Fold in the juice and zest from 2 lemons and 1 ½ cups of fresh blueberries.

Pour the batter into the prepared baking dish and bake for 40-45 minutes, or until a toothpick comes out with moist crumbs.

Allow the cake to cool in the pan for about 10 minutes before transferring to a wire rack. Let it cool completely before glazing.

Whisk together 1 cup of powdered sugar and 2 tablespoons of lemon juice until smooth, and drizzle over the cooled cake.