1. First make the pickled onion. Put the onion into a bowl and sprinkle with the sugar, cloves, vinegar and a pinch of salt. Toss well to mix, place a saucer or layer of cling film over the onions and weigh down with a can of jar. Leave while you prepare the salad, or for up to an hour. --- 2. To make the dressing, put the mustard, honey, vinegar and oil into a bowl, add a pinch of salt and pepper and stir to combine. Taste and adjust the seasoning as necessary. Set aside.

3. Place the watercress, lettuce, apple, celery and radishes in a bowl and mix together. Mix the dressing again, pour it over the salad and toss to ensure everything is lightly coated. --- 4. Dot pieces of the ham and cheeses over the top. Drain the pickled onion and dot this over too. Toss lightly and serve.