Rub the potatoes well, then cook them in lightly salted water until tender. Drain and cool, then cut them into bite-size chunks.
EITHER: During the boiling put a steaming basket above the potatoes and steam the peas and green beans for 5 minutes.
OR: blanch the vegetables for 2-3 minutes in the cooking water of the potatoes then drain.
Toss the vegetables in a large serving bowl.
In the meantime, remove the seeds and veins of the chilli. Chop finely the flesh. Slice the onion thinly and diagonally.
Heat 1 tbsp of oil in a frying pan and cook the spring onion and chilli for 1-2 minutes until soft.
Remove from the heat, add the remaining oil, vinegar, honey mustard, mix well. Pour over the vegetables. Season with salt & pepper.
Serve it warm.