1. Preheat oven to 350°F. Grease and line two 8-inch round cake pans.

2. Combine milk, lemon juice, and yogurt. Let sit 10 minutes until slightly curdled.

3. Add lemon zest and sugar, whisk until dissolved. Stir in oil until smooth.

4. Whisk together flour, cornstarch, baking powder, baking soda, and salt.

5. Add dry ingredients to wet mixture and mix until smooth.

6. Toss blueberries in flour then fold gently into batter.

7. Divide batter between pans and bake 25 to 30 minutes until toothpick comes out clean.

8. Cool in pans 30 minutes then transfer to wire rack to cool completely. Trim tops level.

9. For blueberry sauce, cook blueberries with water until soft. Pass through a sieve and cool.

10. For buttercream, beat butter until fluffy. Add powdered sugar in additions. Add blueberry sauce and whip 10 minutes.

11. For lemon curd, whisk milk, lemon juice, sugar, and cornstarch in saucepan over low heat until thickened. Stir in butter and turmeric. Cover and refrigerate 1 to 2 hours.

12. Assemble by spreading buttercream on first layer, fill well with lemon curd, top with second layer.

13. Apply crumb coat and refrigerate 30 minutes. Apply final frosting and refrigerate 30 more minutes.

14. Decorate with fresh blueberries and spoonfuls of lemon curd on top.