Mapo tofu, Chen Mapo's 1950s recipe

Cover the pork bones and beef shin with cool water, bring to a boil and blanch about three minutes; drain and rinse.

Add three litres of cool water, the Shaoxing wine, smashed ginger, knotted scallion and optional Sichuan peppercorns.

Bring to a boil, skim, and simmer on low four to five hours. Remove the meat; keep 300 ml of stock and freeze the rest.

Mince the douchi in advance.

Trim the stems from mixed dried chilies, toast lightly and grind to a powder.

Cut the soft tofu into roughly one-inch cubes, soak in salted hot water a minute or two, drain and set aside.

Heat half a cup of oil in a wok over medium-high until bubbles form around chopsticks; add the minced beef and fry six to seven minutes until past done, slightly golden and the oil clears.

Add the salt to the oil, mix, then add the douchi and smush and fry it evenly into the beef, thirty to sixty seconds.

Add the chili powder; once fragrant, about fifteen seconds, add the stock and bring to a simmer.

Add the tofu, cover with a bamboo lid or a loose lid that allows some reduction, and cook about three to four minutes, until reduced by about a quarter.

Mix in the chopped scallions, then the soy sauce and MSG.

Thicken with a slurry of about two teaspoons of starch and a little water.

Add half the Sichuan pepper, plate, and add the rest at the table to taste. Eat immediately.