Mandolin blueberries squares | Cake recipe

Ingredients

• 180 ml (3/4 cup) of flour
• 75 ml (1/3 cup) of brown sugar
• 310 ml (1 1/4 cup) of oat flakes
• 2.5 ml (1/2 teaspoon) of baking powder
• 575 ml (2 1/3 cups) of butter
• 1 big egg
• 100 ml (1/2 cup) of sour cream
• 475 ml (2 cups) of blueberries, strawberries
• 60 ml (1/4 cup) of sugar
• 45 ml (3 tablespoons) of water
• 15 ml (1 tablespoon) of cornstarch