Put a large non-stick frying pan on a medium high heat
Add the plain flour, bicarbonate of soda, baking powder and (if using) caster sugar to a large mixing bowl and stir together till well combined
In another bowl or a large jug, whisk together the egg, buttermilk, milk and vanilla extract
Slowly pour the buttermilk mixture into the bowl of flour, whisk them together as you pour and keep whisking until fully combined and the batter is smooth
Add spoonfuls of the batter into the frying pan, leaving space between each one
Cook for around 2 minutes, then flip over and cook for 45-60 seconds on the other side
Keep an eye on the heat, the pan should not be smoking and the pancakes should be golden. Adjust the heat as necessary
Serve the pancakes imediately with your chosen toppings
Leftover and fully cooled pancakes can be kept in the fridge for 2-3 days, or frozen for up to 3 months. To re-heat, once defrosted place the pancakes in a warm (but not too hot) frying pan for a few minutes. Turn over reguarly. Or microwave fpr 30-60 seconds