Preheat the oven to 180 degrees C. Grease and line a 28cm round cake tin.
Place all the crumble ingredients into a food processor and process to form fine crumbs.
Cream the butter and sugar together until light and creamy. Add the eggs one at a time, beating after each addition. Fold in the sifted dry ingredients, alternating with the sour cream. Try to start and finish with the dry ingredients.
For the cake:
Spread half the cake batter into the base of the tin and sprinkle over the berries. Top with the remaining batter and sprinkle crumble topping on top.
Bake one hour or until a skewer inserted in the cake comes out clean. Cool in the tin before turning out.
I cooked this in a 10" springform pan at 350 degrees F for 1 hour and 20 minutes. In the future, I will cook at a 375 temperature. I didn't have caster sugar, so I just pulsed regular sugar in the food processor to reach a fine texture, and used strawberries instead of raspberries. Great moist cake texture, with a layer of fresh fruit in the center, and a rich and buttery-cinnamon crumble on the top. Very nice recipe. - 21 May 2013