1 ½ cups all-purpose flour
1 cup white sugar, divided
1 ½ tsp baking powder
½ cup butter
2 tsp vanilla extract, divided
4 cups blueberries
2 cups sour cream
2 egg yolks
1 Preheat the oven to 190C. Grease a 23cm pan with butter.
2 In a medium bowl, stir together the flour, ½ cup of sugar and baking powder. Mix in the butter by pinching between your fingers or using a pastry blender until the mixture resembles coarse crumbs. Stir in the egg and 1 tsp of vanilla. Pat lightly into the bottom of the prepared pan. Pour the blueberries over the top.
3 In another medium bowl, whisk together the sour cream, ½ cup of sugar, egg yolks and 1 tsp of vanilla until smooth. Pour over the berries.
4 Bake for 60 to 70 minutes, until the top is lightly browned. Cool, then run a knife around the edge of the pan. Remove the outer ring of the pan and cut into wedges to serve.