An odd ingredient, one that isn't readily accessible in the stores around here at least, is dried orange peel. Apparently you can buy it pretty easily in Hawaii. What I did for this ingredient is I used a vegetable peeler to strip off a long strip of peel (just the zest) from an orange. This I set on a shelf in my kitchen for a week to dry out. It worked great. I wondered why one would use the dried and not fresh orange peel and I think perhaps it's because of the long cook time; maybe the dried peel holds up better to long cooking? If I didn't think ahead to dry the peel, I would just use a couple teaspoons of orange zest instead.
- 2 lbs oxtails
- 1 strip dried orange peel (zest, not the pith)
- 2 star anise
- 1 2-inch piece of fresh ginger, thinly sliced
- Salt, at least a tablespoon, more to taste
- 1/2 cup of shelled, skinned, raw peanuts (can sub roasted unsalted peanuts)
- 1/8 teaspoon chili pepper flakes (or more to taste)
- A handful of fresh mustard greens, coarsely chopped (about 2 cups, loosely packed)
- Fresh cilantro, chopped
- Green onions, white and green parts, sliced on diagonal
- Freshly grated ginger
1 Bring a large pot (5-quart), half filled with water, to a boil. Add the oxtails. Parboil for 30 minutes. Drain the pot. Rinse the oxtails in water. Trim the oxtails of any excess fat.
2 Return the oxtails to the pot. Cover with water by an inch. Add the orange peel, star anise, ginger, and salt. Bring to a boil, reduce to a simmer. Cover and let simmer for one hour. Add the peanuts and simmer for 2-3 more hours, until the oxtail meat is tender and falling off the bone.
3 At the point, you can either skim the fat off the soup and proceed to the next step, or let the soup cool, and chill it overnight in the refrigerator. The next day the fat will have solidified and will be easy to pull up from the top of the soup. The flavors will also have had more of a chance to blend and be absorbed by the oxtails if you let the soup sit overnight.
4 Bring soup to a simmer. Add the chili pepper flakes and mustard greens. Cook for 5 more minutes, or until the mustard greens are tender.
Serve with garnishes of chopped fresh cilantro, green onions, and freshly grated ginger.
If you want, you can strip the meat off the bones before serving. We prefer the meat served bone-in, in which case you will want to provide a bowl for the bones.