Boil the potatoes in a pan of boiling salted water for 15 minutes. Add the green beans; cook for 4-5 minutes until just tender.
Meanwhile, mix half of both zests with the crushed peppercorns; press on to the pork.
Heat 1 teaspoon of olive oil in a nonstick frying pan, add the pork and fry over a high heat for 2 minutes each side.
Put the remaining zest in a bowl with half the lemon juice. Mix with 2 teaspoons of olive oil to make a dressing; season.
Whisk the rest of the lemon juice, the orange juice and honey together. Pour into the frying pan and bubble for 2-3 minutes until syrupy, turning the pork to glaze in the sauce.
Remove the green beans with tongs, toss with the dressing and divide between 2 warmed plates, leaving any dressing in the bowl. Drain the potatoes, add to the bowl and crush lightly with a fork. Serve with the pork and sauce.