Blueberry Cake with Buttermilk & Cinnamon Streusel

Preheat the oven to 180 °C (top/bottom heat). Line a baking dish (approx. 25 cm x 15 cm) with baking paper.

For the streusel, combine 90 g flour, 50 g sugar, 50 g butter, and 5 g cinnamon in a small bowl until a crumbly mixture forms. Set aside.

In a large bowl, mix 170 g flour, 80 g sugar, and the baking powder. Add the egg, 150 ml buttermilk, and 30 ml rapeseed oil, and stir everything into a smooth batter.