Bring a large pot of water to a boil. Put it all the oxtail and blanch for about 1 minute. Discard the water and set the oxtail aside. Wash and clean the pot or use another clean large pot
Cooking on the stove:
Melt about 3 Tbsp of butter in the pot. Add in the garlic, stir-fry for about 10 seconds, add in the cloves, peppercorns, bay leaves and nutmeg powder and stir-fry until really fragrant. Add in the oxtails, beef broth and celery, and water, just enough to cover the oxtails. Put in the cinnamon stick and bring to a boil and then lower the heat, cover, and let it simmer for the next 3-4 hours (or until the oxtails are really tender)
About 15 minutes before the end of boiling the oxtails, add in the carrots, tomatoes and potatoes and let them cook until veggies are soft but not mushy. Remove the celery and discard. Have a taste and season with more salt to your liking. Skim off some of the fat before serving if you prefer. Sprinkle some fried shallot crisps and cilantro leaves on top of the soup and serve with the chili sauce on the side
Cooking with Instant Pot pressure cooker:
Press saute on Instant Pot. Melt about 3 Tbsp of butter in the pot. Add in the garlic, stir-fry for about 10 seconds, add in the cloves, cinnamon stick, peppercorns, bay leaves and nutmeg powder and stir-fry until really fragrant. Add in the oxtails, beef broth and celery. Close the lid. Turn the steam release valve to sealing. Press "pressure cooker" and make sure it's on "high pressure". Set the timer to 45 minutes. Wait 10 minutes and then release pressure
Press saute mode again. Add the potatoes and carrots. Cook until they are soft, about 10 minutes or so. Add the tomatoes and cook until the tomatoes are soft but not mushy. Have a taste and season with more salt to your liking. Skim off some of the fat before serving if you prefer. Sprinkle some fried shallot crisps and cilantro leaves on top of the soup and serve with the chili sauce on the side
Notes
If you use pressure cooker, the cooking time will be much shorter, refer to the manual of your pressure cooker.