In a medium bowl combine the flour, baking powder, sweetener, milk, eggs and vanilla extract. Mix until you have a smooth batter.
Add the blackberries and gently combine until they are all covered in batter.
On a hot plate or large frying pan, heat a few sprays of oil then pour approximately 1/4 of the mixture (ensuring there are some blackberries in there) onto the pan. Heat until bubbles start appearing then flip the pancakes over.
Heat the reverse side for a minute then remove. Repeat until you've used all the mixture.
Serve with fresh blackberries and low-fat Greek yoghurt.