1 Little Gem lettuce, leaves separated
100驳/3陆辞锄 Portobello mushrooms, finely chopped
1/3 cucumber, sliced
陆 small onion, finely chopped
2 tsp finely chopped fresh thyme (or 陆 tsp dried thyme)
120g/4陆oz cherry tomatoes, sliced
250g/9oz extra-lean beef mince (under 5% fat)