Spinach made in Hong Kong

About 10 years ago my parents ate in a restuarant in Hong Kong and were served spinach along with their main course. They both said it was the best vegetable they had ever eaten. (And they both are veggie lovers) Their waiter spoke no English, so he couldn't begin to tell them what was in it.

Any good Chinese cook who might help? They had no idea what other flavor might have been in it; they both said it was spinach, not Chinese greens (although a few might have been included).