In a large frying pan heat oil or ghee over medium heat and add cumin, mustard seeds, & cardamom if using. Stirring constantly, heat until fragrant, ~2 minute Add potatoes & onions and saute until onions are golden brown, ~ 5 minutes.
Add greens & 1/2 cup water if needed. Bring to a boil then lower to a simmer, cover and cook until your greens are done ~10 minutes, stirring occasionally. Add chickpeas at the same time as the greens if using.
Serve with a dollop of yogurt, on naan or over rice!