Sift the flour into a bowl and carefully mix with the whole wheat flour, baking powder, baking soda, cinnamon and nuts.
Cut the strawberries into large pieces.
In another bowl, crack open the egg and whisk gently. Then add sugar, oil, vanilla sugar and the yogurt and mix together. Then add the flour mixture and finally fold in the strawberry pieces carefully. Place 12 muffin paper cases in the tray and fill in the batter.
Bake in a hot oven for approx. 20-25 minutes until golden. Let rest in the tray for 5 minutes, then carefully remove and allow to cool.