Whisk the eggs with water and milk. Add flour and salt and stir everything into a smooth dough.
Leave the butter out in a non-stick pan and fry the onion cubes until translucent. Put the onions in the batter. Also stir in the ham cubes, salami and Gouda cheese into the batter.
Heat about 20 g margarine per pancake in a pan and add about 2 ladles full of batter. As soon as the dough has set, slide the pancake onto a plate, slide it upside down and slide it back into the pan and finish baking.