2) Place 30ml of the melted butter into a 25cm cast iron frying pan and place in the oven.
3) Set the remaining 15ml of melted butter aside to cool slightly. Wait 10 minutes before assembling the other ingredients.
4) Place the flour, vanilla sugar, salt, milk, eggs and 15ml cool melted butter into the bowl of a food processor or blender and process for 30 seconds.
5) Carefully pour the batter into the preheated frying pan and bake in the centre of the oven for 30 to 35 minutes or until the edges are puffed and brown.
6) Sprinkle with vanilla sugar and serve with lemon wedges.