Season the oxtails with salt and pepper to taste.
Heat the vegetable oil in a large pot or Dutch oven to medium-high heat and brown the oxtails on each side, 3-4 minutes each. Set them aside.
Reduce the heat to medium and add the onion, peppers, and green onions. Cook, stirring, 3-4 minutes.
Add the garlic and cook 1 minute, stirring.
Add the Scotch bonnet pepper, tomato paste, Worcestershire sauce, curry powder, paprika, all spice, and more salt and pepper to taste. Cook, stirring, for 1 minute.
Add 1 cup beef stock to deglaze the pot. Scrap up any browned bits from the bottom of the pot.
Tuck the browned oxtails back into the pot and pour in remaining beef stock.
Bring to a boil, then reduce heat, cover, and simmer for 2-3 hours, or until the oxtails are tender to your liking. Skim excess fat from the top, if desired. You can shred the meat if you’d like, or serve it with the bones.
Add the carrots and potatoes. Cover and simmer 30 minutes to soften.
Stir in the butter beans and simmer 5 minutes to warm.
Stir in parsley and serve.