Heat oil in a large pot over medium until hot, and then sear the oxtail, stirring frequently, scraping browned bits off the bottom until they're brown. Remove excess oil.
Add onions, green onions, garlic, thyme, and smoked paprika, and stir for about a minute. Toss in the scotch bonnet pepper, tomato paste, and bay leaf, and stir for another minute.
Add about 6 cups of water and chicken bouillon, bring to a boil, and simmer until tender (depending on the oxtail size and preference) for 2-3 hours, occasionally stirring.
Add carrots and potatoes 15-20 minutes before it's done. Adjust the thickness of the soup with water or stock. If you want it thicker, add a cornstarch slurry.
Adjust the seasoning with salt to taste. Remove the bay leaf and serve hot.
Notes
The perfect make-ahead, it tastes even better the next day.
This recipe freezes well if you leave out the potatoes.
Please remember that the nutritional information is a rough estimate and can vary significantly based on the products used in the recipe.