Cut the pickles into thin slices. Rinse the tomatoes and the lettuce and pat dry. Cut the cheese with a cookie cutter into small circles. Cut the buns in half. Mix the ground beef with the mustard, season with salt and pepper, knead and divide into 6 portions. Shape each into a ball and flatten. Heat the clarified butter in a pan and cook the hamburgers in batches until golden brown on both sides.

Top the bottom half of the bun with some lettuce and place a hamburger on top. Top with cheese slices and add the halved olives to make eyes. Cut the tomatoes into small wedges and place as the mouth, arrange some lettuce and watercress as hair and some pickle slices as a bowtie. Serve the top buns.