1.Boil, steam or microwave potato until just tender; drain.
2.Meanwhile, using vegetable peeler, peel random strips of skin from eggplants and zucchini; discard skins. Halve each vegetable lengthways; cut halves into 3cm pieces.
3.Heat 1 tablespoon of oil in wok; stir-fry eggplant and zucchini, in batches, until browned lightly and just tender.
4.Heat the remaining oil in wok; stir-fry potato, in batches, until browned and crisp.
5.Heat remaining oil in wok; stir-fry onion, garlic, beans and peppercorn until beans are just tender.
6.Return eggplant, zucchini and potato to wok with stock, vinegar and sauces; stir-fry until hot. Remove from heat; stir in basil.
In addition to the chilli heat we associate with this regional Chinese cuisine, Sichuan cooking often includes eggplant and green beans; we’ve added potato and zucchini for a twist. Try to find a variety of potato known as Idaho or Russet Burbank for this recipe, as it’s a great one for browning and crisping.