Place the potatoes in a large pan of boiling water and cook for 8-10 minutes until tender.
Add the green beans and cook for a further 2 minutes before draining.
Transfer the potatoes and green beans to a large bowl.
Add the cannellini beans, red onion, tuna and herbs.
In a small bowl mix the oil, pesto, lemon juice and season.
Fold through the salad and spoon onto plates to serve.
Our thanks to the Potato Council for providing this recipe.
Try one of our other tuna recipes, including potato, fennel and tuna bake and tuna melt toast. Alternatively, try one of our other potato recipes.