Take your oxtail and cut slits parallel to the bone on the medium to large pieces.
Place the oxtail into your Instant Pot. Followed by 2 teaspoons of salt, 1 teaspoon of pepper, 1/2 a large onion cut into fourths, and 5 cups of water.
Secure the lid and set the steam release to the “sealing setting.”
Set the Instant Pot at high pressure on the "meat / stew" setting for 45 mins.
When it is done, quick release the steam release until the float valve unlocks so that you can safely remove the lid. (Be very careful at this step, some hot liquid may spew out of the vent. We recommend you use oven mitts and slowly turn the valve until only steam is coming out of vent.)
Julienne cut the other half of the large onion and sauté it in 2-3 tbsp of oil in a separate pan.
Once the onions are translucent, add 4 minced cloves of garlic to the pan and sauté them until they’re fragrant.
Add in 2 teaspoons of annatto powder in pan, and mix until the powder is dissolved.
Transfer all of the oxtail into the pan and coat them with the sautéed ingredients. Once coated, remove the oxtail from the pan and set aside for later.
Add about 4 cups of oxtail broth left over in the Instant Pot to the pot with the sauté, and let it simmer over medium high heat. Submerge 1 Chinese eggplant (cut into 1 inch pieces), and 3 bunches of baby bok choy (with the stems cut off).
Place the lid over the pan and cook the vegetables for about 2 mins. Then remove the bok choy and set aside. Continue to cook the eggplant for an additional 3 mins. Then remove and set them aside as well
Once all the vegetables are removed from the pan, you can add salt to taste the remaining broth, if needed.
Add 1/2 a cup of creamy peanut butter to the broth and mix over medium heat until your sauce thickens to your liking.
When the sauce is done, add the oxtail back in and coat them in the peanut sauce. And then add in your eggplant and bok choy as well. And you’re done!
