Liu's answer is to add a dollop of pork jelly to decrease the temperature and the sweetness.

"We're still working on the 'meatballs thrown by the master's wife'. It takes too much time and effort to make the dish. One chef can only throw enough meat to make 10 meatballs at a time, which takes three hours."

Juqi's signature dishes are also on the menu along with the Deyunshe branch's specialties.

The eatery asks diners to write on the duck with edible ink before roasting so they can be sure the duck that ends up on their plate is the one they selected.

Liu used to work for China's celebrated Quanjude roast-duck restaurant.

He has designed an oven that simulates traditional charcoal-fire roasting and controls the temperature to ensure ducks are tender inside and crispy outside.

Juqi fried rice is one of the chain's signature dishes. Liu has developed five versions.

The dish is shaped like a honeycomb briquette, which were commonly used in Beijing before the 1980s.

"I used black rice in the first version," he says.

"But the texture wasn't satisfactory. So, I used squid ink to dye regular rice in the second round."

He now instead colors the rice with a black tree sap. Two versions are available-a saccharine option with chopped fruit and a salty kind with sausage and other preserved meats.

The Beijing rabbit god-shaped mashed potatoes have a bacon-salad filling with mustard and pickled cucumbers. It's colored with pumpkin puree.

"Each dish is a puzzle for me," Liu says.