Preheat oven to 180°c
Cream the sugar and butter
Mix in the vanilla extract & lemon zest
Slowly add the beaten eggs mixing in-between pours
Sieve the flour on top, add the baking powder. fold in with a wooden spoon
Lastly add the yoghurt, mix well until you have a thick silky batter.
Toss the Raspberries in 2 tablespoons of plain flour, set aside
Line a loaf tin with baking paper
Put a third of the cake batter in the loaf tin
Sprinkle raspberries on top
Cover with a layer of cake batter
Sprinkle more raspberries on top
Cover again with a final layer of cake batter
Bake for 40 minutes