To PrepTo make the lettuce cups, remove the outer layer of the lettuce and cut out the stem of the lettuce. Remove the leaves of the lettuce and trim them in to cup shapes with enough space to put the fillings in to them. Store the trimmed leaves in a large bowl of cold water and keep cool until they are served. To CookIn a large pan or wok, add 1 tbsp of oil and saute the garlic and green onions until fragrant. Add the mushrooms, carrots and water chestnuts in to the pan and stir-fry for about 2 minutes.Add in the snow peas and chilli and continue to stir fry for another 2 minutes.Add in the Shaoxing wine and cook until almost all of the liquid has evaporated. Add in the oyster and soy sauce and stir until well combined before adding the cornflour mixed with 2 tbsp of cold water. Stir the cornflour mixture until the sauce begins to boil and thicken before removing from the pan.To serve, place a couple of the lettuce leaves on to a plate and fill with the vegetable filling.