Clean and dry the vegetables.
Cut tomatoes into six slices each. Halve each of the two types of cucumber and also cut into slices. Top each lettuce leaf with slices of pickles, cucumbers and three tomatoes.
Arrange a few onion rings on top if desired. Garnish each with a teaspoon of ketchup and a few chive rolls. The ingredients can of course be changed and jazzed up according to taste.