Preheat the oven to 240°C/fan 220°C/gas mark 9. Put a non-stick muffin tin in the oven for 5 minutes. Melt the butter in the microwave. Warm the milk on the hob until it's lukewarm.
Whisk two eggs in a bowl, then add the warm milk and mix. Mix in the vanilla extract, then add the flour and whisk until smooth.
Remove the muffin tin and brush the moulds with the butter. Ladle in the batter and put into the oven for 15 minutes until puffy and golden.
Meanwhile, heat the blueberries and maple syrup gently over a low heat for 15 minutes. Gently shake the pan every couple of minutes. To serve, dollop the pancakes on top of the pancakes while they're still warm and add cooked bacon, if liked.