Whisk the egg whites with a pinch of salt until they hold firm peaks.
In a large bowl, whisk together the egg yolks, caster sugar, and salt. Add in the milk. Then the flour and baking powder, whisking just until just smooth.
Gently fold the whipped egg whites into the egg yolk mixture.
Heat a large frying pan over medium heat. Add the butter and pour batter into pan, spreading it into a large pancake.
Cook for approxiamtely 3 minutes, checking underneath occasionally to make sure it doesn't burn, until it’s a golden brown; reduce the heat if the pancake is browning too quickly.
Using a wooden spatula, divide the pancake into 4 and flip each fourth over. Continue cooking until golden underneath on the second side, around 3 minutes.
Now, add more butter to the pan, and tear the pancake into smaller pieces. the inside of the pancake will still be runny at this point. Cook, adding more butter if needed, until just cooked through.
Serve with a dusting of icing sugar and berries. I'm partial to cottage cheese, but also love a dollop of fromage blanc.