Dust the blueberries with cornstarch
.Pre-heat the oven to 160°C/350°F. Grease a 10 inch springform pan generously with cooking spray and set aside.
In a small bowl mix together flour, baking powder and lemon zest.
Cream together the butter and sugar at high speed in a stand mixer – about 2 to 3 minutes. Add egg yolks a little at a time and continue mixing an additional 2 minutes.
Add yogurt and continue mixing. Sift in the flour mixture into the batter, and then add vanilla extract and lemon juice.
In a separate bowl, beat egg whites until soft peaks form.
Using a spatula, gently fold in the beaten eggs whites into the batter.
Stir well until everything is fully combined. Scrape down the sides of the mixing bowl.
Pour half of the batter into the greased cake pan and spread evenly. Top with half of the blueberries. Spread with remaining batter then place the rest of the blueberries evenly over the top.
Tap pans on work surface to eliminate any large air bubbles.
Bake at 350 F until a tester inserted into the center comes out clean – about 50 -55 minutes. Transfer to a wire rack.
Let cake rest in the pan for about 20 mins then remove ring and let it cool. Don’t be tempted to remove before then.
Dust with powdered sugar.