As winter arrives in Beijing, a wide range of long-established restaurants are helping diners keep the chilly temperatures at bay.

During the cold weather, long lines of customers form outside the Shaguoju restaurant, which is widely known for its eponymous special dish that combines hot soup and delicately cooked streaky pork.

Cong Lei, 36, the eatery's general manager, said shaguo bairou, the name for this dish, which translates as "a casserole with meat", is highly popular.

"Diners are eager to taste this dish made from pork and vegetables cooked slowly in an open-fire oven."

Having worked in the catering industry in Beijing for 12 years, Cong said she is not a picky eater and does not have many favorite dishes, even at the restaurant she works for.

She added: "The dishes all taste good. If I had to name one, I would choose sesame seed pancake, as I eat it frequently and it has a beautiful name, yuanmeng (dream coming true) pancake."

The dish is served with crackling pancakes and fried minced pork.

According to Cong, the Empress Dowager Cixi (1835-1908) dreamed of eating yuanmeng pancake one night, but did not tell anyone. By coincidence, her chef cooked this dish and served it during a meal. The pancake got its name, as the empress was delighted and her dream was realized.

Founded in 1741, the Shaguoju restaurant serves imperial cuisine and traditional Beijing dishes.

Located in Xisi South Street, Xicheng district, it can cater to 500 customers at a time, covers three floors, has the same number of dining halls and boasts 10 private dining rooms with traditional-style furniture and decorations.

Cong said the "busy season" started in October and the restaurant is taking more than 100,000 yuan ($15,214) each day.

In autumn and winter, it is always crowded, with customers waiting at least half an hour for tables from midday.

Cong said: "Shaguoju is popular not just because the food tastes good, but also because the dishes are customer-friendly. They are cooked in a traditional, simple way and are reasonably priced.

"Most of our customers are more than 50 years old and dining here is a daily habit for them."

Yang Xin, a 35-year-old Beijinger, said she first went to the restaurant when she was a child.

"My grandpa likes it a lot. Even though we don't live nearby, we still go there often for a taste of the past. It used to be relatively expensive and it was a treat to eat there when I was a kid. However, the prices nowadays are very reasonable."

For Spring Festival, which next year falls in February, all the private dining rooms at the restaurant have been reserved for Lunar New Year's Eve.

One of the reservations was made by a local family that has used the same dining room on the eve of the festival for the past seven years.

Every year, the great-grandfather of the four-generation family, whose surname is Su, invites a professional photographer to take pictures of the annual gathering.

Su, 84, said:"I like to eat at a familiar place and see younger members of my family growing up. Life changes, but love stays in this family in this familiar dining venue."