Purple sweet potato & black bean garlic dumpling filling

If you follow me on twitter, you may have noticed that the last couple years I've been cooking more Chinese foods which was started by a mapo tofu recipe video from Chinese Cooking Demystified. We now have a number of cooking implements, including an induction wok unit, and stock a range of pantry staples for Chinese recipes. "Fried rice", a dish that I'd attempted in the past and failed at repeatedly, is now something we do routinely to use up leftovers.

So with that background out of the way, this recipe came up as a riff on various other ideas to try to make a tasty savory dumpling (jiaozi) filling that was vegetarian and would appeal to the kiddo. A few months ago I started trying to make dumplings from scratch. Rolling out wrappers and filling dumplings as a family is fun! Unfortunately, the most common veggie fillings I would see were various combos of minced cabbage, mushroom, carrot, etc. or egg and jiucai (Chinese chives) and the kiddo wasn't too into them. So we'd been making a chicken & cilantro recipe as one of the fillings. I don't recall how I got the idea of using purple sweet potato & black bean garlic sauce but likely I had just made some other kind of black bean garlic dish and we had purple sweet potato on hand.

"Black bean" in this recipe is actually something called douchi and is a fermented dark soy bean. At least here in Seattle, finding bags of kind it is trivial. If've you seen little black flecks or chunks in a mapo tofu, that was probably douchi. Black bean garlic sauce is a pounded mixture of the bean and other sauces (like soy sauce), garlic, maybe shallot, sugar, salt, etc. The Chinese Cooking Demystified had a Patreon-posted recipe for black bean garlic braised lotus root (or other starchy veg) that had become a household staple and it involves pounding together the various ingredients and then quick frying the "sauce" in oil, then adding chunks of starchy veg and simmering for a w while to get a lovely gravy covered braised dish.

I'm still iterating on this recipe and this is approximately the most recent version of it. Once you have a filling you would put into dumpling wrappers, and then cook the dumplings however you would cook. Our usual method can be seen in the chicken & cilantro recipe linked above – essentially pan fry for a bit with a little oil, then add water and cover and let steam to finish.

Ingredients

• 600 g purple sweet potato. You could probably use other kinds, but it wouldn't be purple.
• 3 tablespoons black bean garlic sauce using this recipe. Note: you make a larger batch ahead and store in the fridge!
• Several tablespoons coconut oil. So, one of the things that is common in meat dumpling fillings is pouring in extra oil or even seasoned oil (e.g. scallion oil) in with minced meat. Without extra fat, a sweet potato mash is pretty bland and just thick.
• 2 egg whites. If you're lazy, you can also include the yolks but a lot of dumpling recipes call for just the whites so that's what I've been mostly doing.
• 2 tablespoon light soy sauce. This is Chinese-style soy sauce, not tamari or Japanese-style which is often saltier.
• 1 teaspoon oyster sauce. We use a vegetarian mushroom oyster sauce.
• 1 tablespoon peanut oil. I was somewhat winging the last attempt and it didn't have quite enough oil when I was mixing. Probably more coconut oil would be fine here.
• 1 teaspoon toasted sesame oil. Another common meat and vegetarian dumpling ingredient.
• Green parts of 2 scallions, minced.
• Salt and msg to taste. I know, I know. But I usually just pinch out some and sprinkle the msg shaker. Say maybe 1/2 teaspoon salt and 1/8 teaspoon msg?

Steps

1. Peel sweet potatoes and cut into chunks.
2. Steam or boil the sweet potato till tender.
3. While still warm, mash sweet potato pretty thoroughly.
4. Fry black bean garlic sauce in oil briefly by heating a pan till pretty hot, lowering heat, adding a table spoon or two of oil, then putting the sauce in and stirring it around well.
5. Add fried black bean garlic sauce to potato mash and stir well.
6. Add salt, msg, soy sauce, oyster sauce and other oils and stir well. You almost want to whip it.
7. Add egg whites and green onion and stir well.
8. Finish with the toasted sesame oil and stir to combine.
9. Fill dumplings and cook them!

Future Variations

The biggest change I would like to try is substituting flax "egg" or some other vegan binder. Another thing I'm still figuring out is how much oil to add. Meat dumplings often have "extra" fat, either by separating out lean and fatty parts of and mincing those separately and combining and then even sometimes adding more oil on top! Given how dense sweet potato is, whipping the fat and other ingredients in seems critical to making something that isn't too dense.

I'm told that posts need "pictures". Unfortunately purple sweet potato dumpling filling is not very pretty and apparently I didn't take any of the most recent batch!