Wash the oxtail as instructed (see recipe post).
Place the oxtail in a bowl, then add the onion, garlic, scallions, carrot, beef seasoning, pimento berries, and browning sauce. Use your hands to rub the marinade into the meat.
Refrigerate overnight or for at least 3 hours.
Melt coconut oil on medium heat, scrap off the marinade and brown oxtail alone. This should take roughly 10 minutes.
Add the onion, garlic, carrots from the bowl to the skillet and saute until soft.
Transfer the contents from the skillet to the slow cooker.
Pour the beef stock/water into the slow cooker.
Now stir in the tomato paste, thyme and dried butter beans. If using canned butter beans, add them 30 minutes prior to finishing.
Set the CrockPot to HIGH mode for 4 hours.
Mix starch and water together, then add the slurry 30 minutes prior to finishing.