This is heavily adapted from Waitrose magazine. It's a great way of using up left-over rice. Serves 2..
Toast the seeds in a dry pan over a low heat for about two minutes.
Mix the lemon zest, juice and tomatoes in a large bowl, then add the herbs, onions and rice and toss until well combined.
Flake in the smoked mackerel, discarding the skin, then pile in the spinach and give the salad another quick toss.
Divide between two bowls and sprinkle with the sunflower seeds.