Dust the blueberries with cornstarch and set aside.
Preheat the oven to 350°F (180°C). Grease a 10-inch springform pan generously with cooking spray and set aside.
Mix the flour, baking powder, and lemon zest in a small bowl.
Cream the butter and sugar at high speed in a stand mixer (2-3 minutes).
Add the egg yolks one at a time and continue mixing for an additional 2 minutes. Then, add the yogurt and continue mixing.
Sift the flour mixture into the batter, then add vanilla extract and lemon juice. Mix gently but thoroughly.
In a separate bowl, beat egg whites until soft peaks form. Gently fold the beaten egg whites with a rubber spatula or mixing spoon into the batter. Stir well until everything is fully combined, scraping down the sides of the mixing bowl as you go.
Pour half of the batter into the greased cake pan and spread evenly. Top with half of the blueberries. Spread with the remaining batter, then evenly place the remaining blueberries over the top.
Tap pans on the work surface to eliminate any large air bubbles.
Bake at 350℉ (180℃) until a tester inserted into the center comes out clean (50-60 minutes, depending on your oven and altitude). Transfer to a wire rack.
Let the cake rest in the pan for about 20 minutes, then remove the ring and let it cool. Transfer it to a plate, and dust with optional powdered sugar.