Traditional Beijing noodles with soy bean paste.

While the dish's deliciousness has won it global acclaim, the abundant fat beneath the crisp skin has increasingly raised health concerns.

Dong Zhenxiang was among the first to re-invent the roasting technique and introduced "super-lean" duck in 1992.

The chef explains he noticed customers' growing demand for healthy fare then.

So he lowered the density of the maltose water applied to the ducks' skin, and prolonged drying and roasting times.

As a result, the birds he serves contain very little fat. But the skin remains crisp and melts in the mouth, while the meat remains soft and delicious.

Da Dong also tweaked other dishes to lower sugar, salt, oil and calories. And the owner nixed dishes made from wildlife or organs.

This, in addition to well-conceived presentation, has made the eatery a big name among not only Chinese but also foreigners.

The first lady's family ate at a table of 10 (the initial reservation was for 13, including Michelle Obama) and had pre-ordered two starters, 10 fried dishes, two Peking ducks and four staples.

In addition to cucumbers, they had pre-ordered five fried vegetable dishes that included braised aubergine, tender bamboo shoots, sauteed bean sprouts, broccoli and asparagus.

Other hot dishes included kungpao fried prawns, stir-fried diced beef, and fried kungpao chicken. These are very common choices among Chinese diners.