Sift the plain flour, caster sugar, baking powder and salt into a large bowl and whisk to combine.
In another bowl, lightly beat the egg, then stir in the whole milk and melted butter until combined.
Pour the wet ingredients into the dry and gently whisk until the batter is smooth with no large lumps, then leave it to rest for 5 minutes.
Heat a non-stick frying pan over medium heat and brush with a little butter.
Pour about 60ml of batter into the pan for each pancake and cook for 2-3 minutes, or until bubbles form on the surface and the edges look set.
Flip the pancake with a spatula and cook for a further 1-2 minutes until golden-brown.
Stack the cooked pancakes on a plate and keep warm while you cook the rest of the batter.
Serve immediately with maple syrup, honey, fresh fruit or whipped cream, as desired.