Pre-heat your oven to 160 degrees. Start your waffle maker so it's nice and hot ready for you to use.
Combine your dry ingredients - the flour, baking powder, caster sugar - in a bowl. In a separate bowl combine the buttermilk, eggs and cooled butter.
Slowly add the liquid ingredients to the dry, whisking to combine. Don't worry if it's slightly lumpy. Add a splash of milk.
Spoon into your waffle maker and cook until done. Lift out of the waffle maker and into the oven to crisp up for around five minutes. Serve!