Rip off and reserve the top leafy half of the mint. Put the stalks in a pan of boiling salted water, then add the beans and peas to cook for 4 minutes.
Meanwhile, halve and deseed the chilli and finely chop with the top leafy half of the mint. Place in a bowl, finely grate over a little lemon zest, then squeeze in all the juice. Add 2 tablespoons of extra virgin olive oil, mix, taste and season to perfection with sea salt and black pepper.
Drain the beans and peas, reserving a mugful of cooking water and discarding the mint stalks.
Pinch the skins off any larger beans, then pour the beans and peas on to a platter, toss with a few splashes of reserved cooking water, then spoon over the dressing.
Drizzle with 1 more tablespoon of extra virgin olive oil and toss together at the table before tucking in.