Preheat the oven to 350 degrees F In a medium bowl stir together 2 1/2 Cups cake flour 1 teaspoon baking powder 1 teaspoon baking soda 1 teaspoon salt

In another mixing bowl combine 1Cup sour cream, room temperature 2 Tablespoons grated lemon zest 1/2 Cup lemon juice 1 teaspoon vanilla extract

In a stand mixer add 1 cup unsalted butter, room temperature 2 cups granulated sugar Beat on medium speed until light and fluffy Then add 4 large eggs, warmed to room temp, one at a time mixing between each addition

Reduce the speed to low and beat in 1/3 of the flour mixture, followed by half of the sour cream mixture  Repeat with another 1/3 of the flour mixture and the remaining sour cream mixture  Beat in the remaining flour mixture until just incorporated

Coat 1 Cup of fresh blueberries in flour, making sure they are fully coated Gently fold the berries into the batter, being careful not to squish and break them

Fill muffin tins 2/3 full Transfer muffin tin to oven and bake for 15 to 18 minutes Transfer muffin tin to a wire rack and let cupcakes cool completely

In a medium saucepan combine 1 Cup fresh blueberries 1/4 Cup water 2 Tbsp sugar 1 Tbsp cornstarch Stir for 15 minutes or until the mixture becomes thick like a jelly

Remove from the heat and strain the mixture through a wire mesh strainer into a small bowl The mixture should make around 1/4 cup of a reduced sauce Place the small bowl in the fridge, for 30 minutes or until cool

In a stand mixer beat 1 Cup butter, softened (unsalted) until light and fluffy in consistency Add in the blueberry reduction sauce

Alternate adding in 2 tbsp whipping cream 2 1/4 Cups powdered sugar Scrape down the sides of the bowl between additions Finally add in  1/2 tsp vanilla extract and beat until everything is fully incorporated

Decorate the cupcakes as desired We use a Wilton 2D tip to create a swirl Top with fresh blueberries and lemon curls for added flair