If you're using a can of diced tomatoes, blend them along with their juice for a few seconds in the food processor or blender, just to break them up.
Heat the oil in a large pot or Dutch oven over medium heat. Add the onion and cook until soft but not brown, about 10 minutes.
Add the garlic, ginger and chili and cook for about 5 minutes to soften.
Add the tomatoes, stir to combine then add the peanut butter (and coriander, if using), stirring it in until smooth.
Stir in the broth add sweet potatoes. Cover the pan and simmer until the sweet potatoes are tender but not falling apart, about 15 minutes.
Add the black beans, peas/corn, greens and cook until the beans and peas/corn are heated through and the greens are wilted.
Season with salt and pepper, and add additional crushed chili flakes, as per your heat preference.