Beat the eggs in another bowl, and then add the melted butter, sour cream, rind and juice of the lemons and the vanilla extract. Mix thoroughly.
Add the wet mixture to the dry ingredients and stir thoroughly. Add the blackberries and mix well.
Pour into a greased and parchment paper lined 1lb loaf tin.
Bake for 60 minutes until golden and firm. It may take an extra 5 or 10 minutes depending upon your oven.
Allow to cool before removing cake from the tin.
Notes
The net carbs will be the total carb count minus the fibre count. Carb count excludes sugar alcohols.Any nutritional analysis on the website is based on an estimate, calculated by http://nutritiondata.self.com from the individual ingredients in each recipe. Variations may occur for various reasons, including product availability and food preparation. We make no representation or warranty of the accuracy of this information.