Start by making your pickles. Cut your onion in half then slice thinly into semi-circles. Place in a jam jar or bowl then add in the rest of the ingredients (you can choose how much sugar you would like to add in depending on how sweet you like your pickles). Give everything a good shake/stir then leave to the side while you bake your eggs. You can keep these pickled onions in the fridge for a couple of weeks.