Place the flour, baking powder, sugar, egg, vanilla extract, salt, zest of one of the lemons, and milk in a large bowl. Use a balloon whisk to mix until combined.
Pour ¼ tbsp. oil in a large skillet, then wipe around with a kitchen towel to cover the pan. Heat the pan on a medium heat until hot. Pour in enough mixture to make three pancakes (approx. ¼ cup of mix per pancake). Turn the pancakes over when bubbles form on top and then burst, and the edges start to look firm (about 1-2 minutes). Cook on the other side for another 1-2 minutes. Repeat with the rest of the mixture - oiling the pan each time - until all the pancakes are cooked (you can keep the pancakes warm in a very low oven whilst you’re making each batch).
Whilst the pancakes are cooking, place the blueberries, water and granulated sugar in a pan and heat for about 5 minutes until the blueberries release their colour and the sugar dissolves. Turn off the heat and put to one side to cool slightly.
To assemble, stack 3 pancakes on each plate. Top each stack with 2 tbsp mascarpone, 1 tbsp of lemon curd and 2-3 tbsp of the blueberry compote. Sprinkle with the remaining lemon zest and serve.