To prepare the compôte, put half the blueberries in a small saucepan with 2 tablespoons of water. Bring to the boil, reduce the heat and simmer for 3-4 minutes until the berries just start to burst. Remove from the heat and stir in the remaining blueberries.
For the pancakes, put the dry ingredients into a large bowl and mix together. Add the milk, yogurt, egg, and vanilla extract, if used. Whisk to make a smooth, thick batter.
Preheat the oven to 140°C,120°C fan, Gas Mark 1.
Grease a large non-stick pan with the oil and heat gently until hot. Drop in 4 heaped spoonsful of the batter into the pan, shaping the pancakes into rounds. After 1-2 mins, flip each pancake using a spatula and cook for a further minute. Keep the pancakes warm in the oven and continue making the pancakes with the remaining batter.
Serve the pancakes with the compôte, a dollop of extra yogurt and lemon zest, if used.