A grand Shanghai 本帮 banquet centerpiece built on a whole skin-on pork knuckle (蹄髈). The knuckle is first simmered until a chopstick passes through, dried, then deep-fried whole until the skin blisters and puffs into a wrinkled 'tiger-skin' (虎皮) — the step called 走油, 'running the oil.' It is shocked in cold water to set the wrinkles, then braised long and slow in soy sauce, rock sugar, and Shaoxing wine until dark, glossy, and falling off the bone. Served whole on a platter, it is a New Year's-eve and feast-table dish, the puffed skin soaking up the sweet-savory braise.
Deep-fried braised pork knuckle is a standing dish of 本帮菜, the home-grown Shanghai cooking that absorbed the techniques of cooks who came to the city and married them to the local taste for 浓油赤酱 — heavy oil and dark-red sauce. The 走油 method of deep-frying the skin to a puffed 'tiger-skin' before braising is widely used across Jiangnan in dishes from this knuckle to 虎皮扣肉, and the finished knuckle is a fixture of the Shanghai New Year's-eve table, regarded by many as making the feast incomplete if absent. The exact origin and date of the dish are unrecorded; it is best understood as the banquet, fried-skin sibling of everyday braised knuckle.
Cut into the knuckle and the dark, glossy skin gives way first — puffed and wrinkled like tiger hide, jelly-soft yet faintly springy, its blistered pores swollen with braising liquid. Under it the fat has gone nearly translucent and the lean pulls away from the bone in moist, dark strands; the whole thing is sweet, soy-deep, and rich without being greasy, because the frying drove off much of the fat. Done well it is meltingly tender, the skin loose and bubbled and saturated with sauce; done badly the skin stays tight and smooth with no 'tiger-skin' at all because it was fried wet or not shocked cold, or the meat is heavy and cloying because the fat was never rendered out.
The whole dish turns on what 走油 does to the skin. A pre-simmered knuckle is patted bone-dry and lowered into hot oil at about 六七成热 (roughly 180-210°C); the water just under the skin flashes to steam and blows a field of fine pores, puffing and wrinkling the surface into 'tiger-skin,' while the frying renders out a good part of the subcutaneous fat so the finished meat is rich but not greasy. Plunging the fried knuckle into cold water exploits thermal contraction — the hot skin shrinks fast and the wrinkles deepen and set, and the chilled fat firms — leaving a sponge-like surface. In the long braise that follows, those open pores drink up the soy-and-rock-sugar liquid, the collagen of the skin and connective tissue breaks down to gelatin over slow heat so the meat falls off the bone, and the rock sugar both rounds the flavor and lacquers the skin to a dark gloss.
Variations
It is best told apart from two kin. Unlike 红烧肉, which is cubes of belly braised without the deep-fry, the knuckle is a whole skin-on joint whose skin is fried to 'tiger-skin' first. And unlike Jiangsu's 水晶肴肉, a cured, pressed shin set cold in its own clear aspic and served as a sliced cold cut, this knuckle is hot, dark, and braised whole. The same 走油 idea underlies 虎皮扣肉 (fried-skin belly steamed over preserved vegetable) and the everyday 红烧蹄髈, which simply skips the frying. Cooks vary the sweetness and how dark they take the soy, and some tuck blanched greens or a few eggs around the platter.
On the Palate
Where Deep-Fried Braised Pork Knuckle sits in the Chinese flavor cloud
Ingredients
Serves 6
How it's made
7 steps · 40 min
- 115 min
Clean a whole skin-on pork knuckle and blanch it from cold water with ginger and Shaoxing wine to draw out blood and scum.
- 290 min
Simmer the knuckle in plenty of water, kept at a bare tremble, until a chopstick passes through but it still holds its shape; lift out and pat the skin completely dry.
Watch outSimmer at a bare tremble until a chopstick just passes through but it still holds shape, then pat the skin bone-dry — wet skin won't blister in the oil, and any moisture spatters violently.
- 38 min
Rub the hot skin with dark soy sauce for color, then deep-fry the whole knuckle in oil at about 七成热 until the skin blisters and puffs into 'tiger-skin.'
Watch outFry the whole knuckle skin-down until it blisters and puffs into wrinkled 'tiger-skin' — that pored, puffed surface is what later drinks up the braise.
- 460 min
Plunge the fried knuckle into cold water and soak it about an hour so the skin wrinkles deepen and set.
Watch outPlunge the fried knuckle straight into cold water and soak it — the sudden chill deepens and sets the wrinkles into that sponge-like skin.
- 55 min
Caramelize rock sugar in a little oil until amber, add ginger, scallion, star anise, and bay leaf, then pour in soy sauce, Shaoxing wine, and water to cover.
- 690 min
Lower in the knuckle, bring to a boil, then braise on low heat, turning now and then, for about 90 minutes until dark and falling off the bone.
- 76 min
Lift the knuckle whole onto a platter, reduce the braising liquid to a glossy sauce, and spoon it over the top.
