White Chocolate and Lemon Kladdkaka with Blueberries

Name: White Chocolate and Lemon Kladdkaka with Blueberries
Prep time: 10 min
Cook time: 25 min
Total time: 35 min
Cuisine: European
Ingredients: 35g (1¼ oz) white chocolate (chopped); 100g (¼ cup + 3 tbsp) butter; 2 eggs (medium); 130g (½ cup + 2 tbsp) sugar; 2 tbsp lemon juice; 1 tsp vanilla extract; 120g (1 cup) spelt flour (see note 1); 75g (2½ cups) blueberries (couple extra for decoration); Icing / powdered sugar (for sprinkling); sprig of mint (optional)