You can add artichokes if you like. I haven't, as they are not my favourite vegetable. I also used roasted red pepper because I had some in the fridge and some Romaine lettuce to add another texture.
Bring a pan of salted water to a rapid boil and cook the trimmed French beans for two minutes, then plunge immediately into iced, cold water to refresh. Drain and set to one side.
Wash and clean the potatoes. Place the potatoes in the pan and cover with cold water. Add a half teaspoon of salt and bring to a gentle boil, simmer until the potatoes slide off a small, sharp knife. Plunge into cold water, cool and drain.
Halve the tomatoes and carefully cut out the core with a small sharp knife. Cut each tomato half into four pieces.
Break up the lettuce and arrange all the ingredients in two bowls. Season generously and drizzle with the red wine vinegar and a little of the reserved oil, ,from the tinned tuna.