Preheat the oven to 350℉/180℃. Place parchment paper on the bottom and 2 sides of the pan. Grease the two sides without parchment paper and then set aside.
In a medium sized bowl, add in the dry ingredients. Stir to combine and set aside.
2 cups all-purpose flour, 2 tsp baking powder, 1 tsp salt
In a large bowl, add softened butter, white sugar, and lemon zest. Beat on medium speed for 2-3 minutes until it's light and fluffy. Make sure to scrap the sides of the bowl.
1/2 cup unsalted butter, 1 cup white sugar, zest of one lemon
Add in the egg, egg yolk, vanilla, yogurt, and lemon juice. Continue mixing on medium speed until smooth.
1 egg, 1 egg yolk, 1 tbsp vanilla, 1/2 cup yogurt, 2 tbsp lemon juice
Mix in the dry ingredients and using a spatula, gently fold until a batter forms. Do not overmix!
Gently toss the blueberries in 1-2 tbsps of flour before adding them into the mixing bowl. This will help absorb any liquid they may have from washing. Then add into the bowl and mix in a few times.
1 1/2 cups fresh blueberries
Spread the batter into the prepared pan evenly and sprinkle extra white sugar on top.
Bake for 35-45 minutes, depending on your oven. It took me 45 minutes. A toothpick inserted in the middle will come out clean. Allow it to cool, slice, and enjoy!