Put the quails in a foil-lined baking tin and brush each with some plum sauce. Cook under a preheated hot grill for 5–6 minutes on each side until golden and just cooked through. Cut each quail into 4 equal sections and place them in a large salad bowl.
Meanwhile, make the dressing by mixing together the chilli, plum sauce, lime juice and oil.
Put the plums, lamb's lettuce and cashew nuts in the bowl with the quail pieces. Add the dressing, toss lightly to combine and serve immediately.