Pre-process the oxtail first. Put the oxtail and some water (not listed in the ingredients) in a large pot over high heat.
When the pot comes to a boil, turn the heat down to low-medium, and simmer for 30 minutes.
After 30 minutes, drain the oxtail into a colander and throw away the simmering liquid. Rinse the oxtail under running water to remove any scum.
Fill a bowl with water, put in the boiled oxtail, and leave to soak for 30 minutes.
Peel the garlic and crush the cloves with the side of a kitchen knife. Cut up the ginger roughly.
You can just use the garlic and ginger as-is, but I put them in 3 fillable tea bags.
Tie up the green part of leeks with kitchen twine.
After Step 4 is done, rinse off the oxtail again under running water, and make sure that blood is not seeping out between the bone and meat.
If there is some blood, rinse it off very well. In Korea, where this recipe is from, they soak the oxtail for 24 hours apparently, but I've simplified it.
Put the garlic and ginger and green part of leek into the Staub cocotte along with the oxtain and water, and start cooking over medium heat.
When it comes to a boil, cover with a lid, and turn the heat down to the lowest possible setting on your hob. Leave to simmer for 1 hour.
After an hour, move the cocotte to the hob with the weakest heat. Set the heat to the lowest possible setting, and simmer for 4 hours.
(You don't need to move the cocotte in Step 12 if you're already using the weakest-output hob in Step 11.)
After 4 hours have passed, open the lid and take a look inside. Because of the unique characteristics of the Staub lid, and because it was simmered over a very low heat, there's almost no change in the water level.
Poke a bamboo skewer through the oxtail to test how tender it is. If it's as tender as you want it to be, it's good.
The soup looks like this at this point. I sprinkled in some rock salt and tried it, and it was already sooo good.
At Step 15, if the meat is still tough, put the lid back on and simmer for another hour. Check again.
Take the leeks out of the pot (after Step 15 or 17) and put in the daikon radish. Set the heat to medium.
When the soup comes to a boil, turn the heat back down to the lowest setting possible, and simmer for 1 to 2 hours.
After 1 to 2 hours have passed, turn the heat off. Season with salt and pepper and the soup is done.
Oxtail soup that hasn't had any water added at all is richly flavored and sublime. We simmer it a bit more every day and enjoy it for about a week.
I add some chopped white leek, salt and pepper, and medium-grind chili pepper just before serving. It's also great as-is, or with kimchi and rice added to turn it into a gukbap...
The tender and juicy oxtail, which is something that the Staub cocotte is so good at producing, is irresistably good. Do try this authentic, richly flavored oxtail soup.
Addendum: This recipe calls for 1 kilo of oxtail, but if you're going to make this with 1/2 or 1/3 the amount...
...use a 18 to 22cm diameter cocotte ronde. Use enough water to fill the pot 80 to 85%.
If you use cheap beef tendon or membranes and make a similar simmered soup...it's close to a white creamy gum tang soup.
The flavor is different but just as deep and rich. I make both soups and combine them when I feel like it.
This is a gukbap (Korean soup) made in the same way, using oxtail and tendon. This is seriously delicious too.
If the fat in the oxtail soup bothers you: Strain the soup, and put it in the refrigerator or freezer.
In a short time, the fat will solidify as shown here. Just scoop this off. This is an easy way I just thought up.
If you are using a regular pan: Follow the recipe up to Step 10; from Step 11 on, keep simmering while observing the soup's progress, adding a little water occasionally as needed.
Although it depends on the size of the oxtail, I think ideally you want to simmer it for about 7 hours or more. This is delicious even if you don't have a Staub cocotte.
Story Behind this Recipe
I've loved oxtail soup since I was single. I always used to make it in a plain straight sided pot. I started making it in a Staub cocotte a couple of years ago, and I've been enjoying a soup with no water added, something that's possible in a Staub. Everyone around me is really into this soup too, so I decided to upload it...
-Just watch the heat level and let it simmer. It's very easy. Please vary the recipe in any way you like.