How to do it
Cook the potatoes in a saucepan of boiling salted water with a lid and when ready drain and leave to cool. Once cooled cut the potatoes into bite size pieces.
While the potatoes are cooking, slice the onion and drain the tuna.
In a fresh saucepan of slightly salted water cook the runner beans for 4-5 minutes then add the kale and cook for 10 seconds and drain.
In a large serving bowl add the potatoes, runner beans, kale and red onion. Drizzle in the olive oil and lemon juice and mix well.
Add the tuna, sundried tomatoes and black olives, lightly mix and serve with a scattering of sunflower seeds.