In a deep pot, heat the oil. Add the garlic. Then add the onion, pimento, and chadon beni. Sauté until the garlic and onion is slightly golden.
Add the potatoes, Add the black pepper and salt. (or any other seasoning you wish such as chive, and parsley). Mix the ingredients. Add a little water and allow the potatoes to cook until soft.
You may have to add a little water every now and again so the potato does not burn.
Remove and set aside. Serve with your favourite chutney.
Notes
The potato should cook quickly. So, don't leave the pot. Turn the ingredients every now and again and test to see if more salt (or pepper) is needed.