Ensure your salmon is de-scaled and make small incisions into the skin, down just into the flesh. Season well with salt, pepper and thyme leaves
Add oil to a frying pan and, when hot, place the salmon in skin side down. Leave the salmon for 2-3 minutes, or until the cooked flesh comes 3/4 of the way up the salmon. At this stage, add butter and baste well. Remove from the heat, flip the salmon over and the residual heat will cook the salmon through
Meanwhile, finely slice the pak choi, shallots and apples and place into a large mixing bowl with the cider vinegar, raisins and cashew nuts. In a large mixing bowl, combine the mustard, juice of 1/2 and lemon and the yoghurt with plenty of salt and pepper. Add this dressing to the herbs and combine to form a salad.
Remove the salmon from the pan and serve alongside the salad!