Wash the oxtail and boil it in hot water with black pepper, cardamom pods, bay leaves, cinnamon stick, and the whole tomato. Once the oxtail is cooked, add salt.

Slice the onions into thin strips and sauté them in a little oil. Add two finely minced garlic cloves and stir well.

Add the green pepper and stir thoroughly. Then add the tomato paste, stir again, add the potatoes, and sauté everything together for about 3 minutes.

Preheat the oven and place an empty casserole dish inside to heat up.

Add the oxtail to the potatoes and onions, mix well, and adjust the salt and black pepper. Stir, then pour in some of the strained oxtail broth. Give it a quick stir and bring to a boil. Transfer everything to the hot casserole dish, cover with foil, and bake for 30 minutes until the potatoes are tender. Uncover and broil briefly to brown the top. Serve with vermicelli rice or plain white rice, as you prefer.