In a large pot, heat the vegetable oil over medium heat.
Add the finely chopped onion and minced garlic. Sauté until the onion becomes translucent.
Add the chopped tomatoes and cook until they are soft and well combined with the onions.
Add the chopped sweet potato leaves to the pot and stir well to combine with the sautéed vegetables.
Pour in the water or vegetable broth and bring to a boil.
Reduce the heat to low and simmer for about 10-15 minutes, or until the leaves are tender.
In a bowl, mix the peanut butter or ground peanuts with a little bit of the cooking liquid from the pot until smooth.
Stir the peanut mixture back into the pot with the sweet potato leaves.
Continue to simmer the stew for another 10 minutes, stirring occasionally to prevent sticking and ensure even cooking.
Season with salt to taste.
Enjoy your meal!