Put the chicken legs skin side down in a snug-fitting non-stick ovenproof pan on a medium heat to crisp up.
Peel the onion, slice into 1cm-thick rounds, then add to the pan and fry for 10 minutes, stirring occasionally.
Stir in the thyme sprigs and 2 tablespoons of red wine vinegar, flip the chicken so it’s skin side up, and roast it all for 30 minutes, basting halfway.
Meanwhile, finely chop the cornichons and pickled onions and place in a large bowl with 1 tablespoon of liquor from their jar, the yoghurt and mustard.
Mix well, then season to perfection.
Very finely slice the cauliflower and any nice leaves, ideally on a mandolin (use the guard!
), or coarsely grate it.
Toss the cauliflower in the dressing to coat, then divide between your plates.
Thickly slice the baguette and sit it on top of the chicken to crisp up for the last 10 minutes, then serve it all together.
