Gather ingredients and prep for chopping
Chop / slice ingredients
Rinse oxtails underwater, then soak them in saltwater for a few minutes. Rinse again and pat dry.
In the large bowl with oxtails: add all the ingredients except bay leaves, dried anise, chicken, or beef stock.
Marinate at least 30 minutes
Heat a large frypan over medium-high heat. When hot, coat bottom with some butter
Quickly sear oxtails on both sides, you will probably need to do two batches.
In instant pot, turn on saute option for 5 minutes, add in tomatoes, star anise, and bay leaves. Place oxtails next. Then add in chicken or beef stock. Close lid.
Switch from sauteing to pressure cook option on high heat. Set the timer for 40 minutes.
When it's done, open the lid, skim all the fats. Taste it and add more salt if needed.
Then add all vegetables in the pot. Turn on pressure cook again with set time 5 minutes.
It's done. When it's ready to eat, sprinkle some fresh ground pepper and garnish with cilantro.