No Ordinary Dumpling: Filling
No Ordinary Dumpling: Filling
Welcome to our No Ordinary Dumpling series, where our chef Brian Yong details the R&D process of how we here at XCJ developed our current recipe for our signature xiao long bao (小笼包), or XLB. He will be analyzing the three fundamental components of a soup dumpling: the dough, the mince, and the jelly (or ‘jelly’ that becomes the soup). In these posts, he’ll share both the highlights — and the struggles — of his development to create a dumpling that we are proud of, as well as a scaled-down, at-home-friendly recipe for anyone interested in making a version of our XLB.
Once you’ve nailed down a tender, pliable, yet still toothsome dough, the next major component is the filling. The filling of a soup dumpling consists of the ‘mince,’ or ground meat mixture, and the aspic, or savory jelly that melts during cooking to become the eponymous ‘soup.’ The foundation of the filling is built upon the mince — the type and qualities of the meat, the seasonings, spices, and aromatics. Note that we differentiate between filling and jelly. The filling is the meat mixture that you’ll eat in solid form in the final XLB; the jelly is the liquid that starts as a solid gelatin mixed within the filling, and melts into hot soup upon final cooking. We approach the mince as an intermediary of sorts. Its purpose is to complement each bite of dumpling skin while also offering a pleasant textural contrast, and flavoring base to the hot soup. During our development process, we focused on three critical aspects for the filling:
Fat Content: The ideal filling is rich and flavorful, but not overly greasy or unctuous. We set out to find the perfect ratio between fat and lean in our ground pork.
Grind Texture: The fineness of the ground meat affects how dense or how crumbly the filling will be; the final result should be not overly tight so that it’s chewy, but also not extremely loose and crumbly.
Overall Balance: XLBs are steamed, foregoing the maillard reaction that fried dumplings (like the Sheng Jian Bao) leverage to add to their flavor and texture. This delicate cooking method in turn calls for a lighter seasoning and overall balance. So for clarity of flavor, only ingredients that accentuated the base meat or jelly were added.
Like with all food recipes, there are many different preferences for how a filling should taste and feel in conjunction with the outside wrapper and the jelly. The R&D for our filling went through several rounds of taste tests with family and friends — constantly iterating and improving on our previous experiment.
After participating in many hours of philosophical debate on what the purpose of an XLB filling is, we would describe it like the drums of a band — it may not always be in the spotlight, but it needs to be consistently excellent to harmonize the sounds of the other musicians.
Ground pork at your average grocery is typically 80/20 — 80% lean, 20% fat — or 85/15, and the occasional 90/10. While these ratios may not seem vastly different, small variances in the fat content of your ground meat profoundly impacts the final seasoning needed, especially in large batches. This is because fat and salt tend to be contrasting flavor profiles — a good rule of thumb: the leaner your meat, the less salt it requires to achieve a well-seasoned flavor.
We started our development process with an 80/20 ratio for our pork XLBs as it was the most readily available, and we immediately liked the balance. (I guess there’s a reason this is the most popular ratio!) However, in our pursuit to never settle and to create something best in class, we also tried a version at 75/25 and 90/10, employing blind taste tests in both scenarios. While the 75/25 didn’t taste noticeably different, it also didn’t add anything to the working recipe. At 90/10, however, the result tasted significantly leaner, with the soup being much less velvety and smooth from the reduction in fat. Conducting these test trials reaffirmed our gut instinct: a 80/20 ratio was the way to go.
With the ratio finalized, we also tested batches using fresh versus frozen pork. Interestingly enough, in small batch A/B tests the contrast was not as large as anticipated and often our taste testers could not pinpoint which was which. However, once the batches were scaled up, the accumulation of small changes in one direction magnified. After doing quality control on multiple bags of dumplings, we could tell that fresh pork was consistently yielding a better flavor in the final filling. Thus, we only operate with all fresh, 80/20 ground pork.
There are two main camps of filling aficionados: the first, those who prefer a looser, more tender filling (we refer to this as “crumbly” in texture); the second, those who like a tighter, more toothsome mixture (I call this “spongy”). To satisfy both parties, we set out to find a grind texture that would strike an appropriate balance between the two (despite admittedly being part of the latter camp ourselves).
In particular, we see the texture of the filling as an important interplay between the liquid soup and soft wrapper. Because the dough is quite supple, it needs some resistance in the form of the meat filling. Because the fat from the jelly and meat coats the tongue, the filling should not add additional heft, or the dumpling may feel too heavy and damp. Eaten together, the filling should allow the overall XLB to still feel light and delicate.
We started with a medium grind, and quickly faced a major drawback. While in chilled form the filling looked and felt reasonably solid, once the jelly cooked and melted during the cooking process, it left behind little voids in the meat that made the filling texture feel too crumbly and lacking substance.
Once we switched to a fine grind, this initial issue of a loose filling was resolved — but the issue of variable cooking times remained. If XLBs are overcooked, even slightly, more liquid is squeezed out of the filling and the resulting meat is dense and hard. To solve this, we carried out a series of tests to find the full window of acceptable cooking times for our XLBs. As it is better to undercook versus overcook, we now list the timing for each batch of dumplings 2 minutes “under” the ideal cook time, as most customers tend to leave dumplings in the steamer for a few minutes extra before eating.
Finding what we call the “minimum effective dose” of additional flavorings in relation to the ground was arguably the hardest part of the filling R&D. While this may not be a problem for home chefs, the process of mincing aromatics like ginger or green onion adds a very high amount of labor costs, especially when these ingredients scale into the hundreds or thousands of pounds.
We now source our ginger from Sky Valley Farms, which provides an excellent frozen ginger that tastes comparable to its fresh counterparts. We then pulverize this finely for the filling. It took us many, many batches of taste tests to find an appropriate ginger because commercial ginger is (interestingly enough) often adulterated with sugar to extend its shelf life. For green onion or garlic, however, frozen simply could not compare to fresh. As a result, we only use fresh green onions for our pork XLBs.
When it came to seasonings, we wanted to create a refreshing flavor profile that would not be overly salty and thus complement the natural umami flavor of pork meat. A combination of light soy sauce and salt did the trick here: a light soy sauce kept the color of the filling more neutral and added the signature soy sauce flavor. It’s worth noting that light soy sauce is actually saltier than its darker counterparts, which are sweeter and thicker. Salt then brought up the rest of the necessary salinity without diluting the pork flavor farther. (For those cooking at home, remember that not all salt is the same level of saltiness! Some brands, like Morton’s, are almost twice as salty as others like Diamond Crystal, so make sure you consider the sodium level across your ingredients.)
The last few key seasonings beyond some plain white sugar are:
Toasted sesame oil: Not the same as regular sesame oil. Toasted sesame oil is pressed from toasted sesame seeds and offers a much deeper, more developed nuttiness. It has a fairly low smoke point, so it should be treated as a delicate oil best for finishing dishes and seasoning marinades or sauces — not subjected to direct, high heat. We also use the highest quality oil from Japan. Cheaper options will be blended, or of a lower quality, which has reduced aromatic compounds and weaker dimension.
Fermented white peppercorn powder (called 胡椒粉): White peppercorn starts as the same berry that ends up as green, red, or black peppercorn. (Green peppercorns are harvested earlier than red or black ones.) The main difference between black versus white peppercorn is the process after picking — instead of being dried, white peppercorns are soaked, releasing its outer layer and thus shedding its color. For white peppercorns used in Asian cuisines, the berries are fermented 2-3 weeks longer than their European counterparts, adding even more funk and complexity to the final filling.
Papery shrimp (虾皮): These tiny dehydrated shrimps add a concentrated shrimp flavor to our pork and shrimp XLBs that regular sized raw shrimp simply could not. They are translated to “papery” shrimp because of how they look against the light — so translucent, they look like thin slivers of paper. Pound for pound, these add far more shrimp and sea umami than regular shrimp (which flavor is mostly derived from the shells instead of flesh) while also adding some color contrast against the pork. This way, our consumers can visually see there is shrimp in their XLB, which makes the flavor connection much more clear.
MSG (or monosodium glutamate): We saved this for last as it is the most misunderstood item on our ingredients list. MSG is a naturally occurring compound found in umami-rich foods like tomatoes, cheese, and seaweed; its rise to international fame (or infamy, depending on how you see it) came with its isolation from kombu into something that could be reproduced at scale in a lab through fermentation. While it still holds a poor reputation, studies of MSG have repeatedly shown it is safe to eat and has no known side effects. The “Chinese restaurant syndrome” headaches are more an indication of existing prejudices than any real allergies, as MSG is found in almost all of our common processed foods (everything from potato chips to instant ramen). We like to use just a touch of MSG as a natural flavor enhancer for our filling as it adds another type of umami — umami comes in many types! — to the overall soup dumpling.
The Filling Recipe
So without further ado, for the second part of No Ordinary Dumpling, we present you with our current filling recipe for XCJ’s pork xiao long bao below. This is version 1.0 that we are really happy with, but since we are always iterating and improving, look out for small tweaks to this in the future!
(453g) - Ground Pork (80/20, Fine Grind)
(10g) - Ginger (Grated) 10g
(25g) - Scallion 25g
(11g) - Salt 11g
(7g) - Sugar 7g
(0.5g) - White Pepper 0.5g
(8g) - Light Soy Sauce 8g
(8g) - Toasted Sesame Oil 8g
(8g) - Garlic (Crushed) 8g
(4g) - MSG or Chicken Bouillon 4g
MSG or Chicken Bouillon are optional but from a food science perspective, will enhance the perceived umami sensation on the palette; if this is something you desire.