Serves 8 as part of an Indian meal
3 Tbsp mild vegetable oil
1½–2 lb (680–900g) potatoes, peeled and cut into ¾-inch cubes
1 medium onion (6oz/170g), finely chopped
3 cloves garlic, minced
1½ Tbsp fresh ginger, finely grated
1½ tsp cumin seeds
1 tsp ground coriander
½ tsp ground cumin
½ tsp turmeric
1 cup (about 150g) chopped tomato, fresh or canned
1½ lb (680g) Swiss chard, stems finely chopped and leaves roughly chopped
1 lb (450g) mustard greens, tough stems removed and leaves roughly chopped
4oz (115g) fresh nasturtium leaves, roughly chopped
1 tsp salt, plus more to taste
¾–1 cup water or light vegetable stock, plus more if needed
½ tsp garam masala
1–2 Tbsp fresh lime or lemon juice, to finish
Fresh cilantro, chopped, for garnish
Lime wedges, for serving
- Heat 1½ Tbsp of the oil in a large, heavy skillet or saucepan over medium-high heat. Add the potatoes and cook, turning occasionally, until golden brown on several sides and nearly tender, about 10–12 minutes. Transfer the potatoes to a plate.
- Add the remaining oil to the pan and reduce the heat to medium. Add the cumin seeds and cook for about 30 seconds, until fragrant.
- Add the onion and chopped Swiss chard stems. Cook for 5–7 minutes, until the onion is soft and beginning to turn golden.
- Add the ginger and garlic and cook for about 1 minute, until fragrant.
- Stir in the ground coriander, ground cumin, and turmeric. Cook for 30 seconds, stirring constantly.
- Add the tomatoes and cook for 5–7 minutes, stirring occasionally, until they have softened and the mixture has thickened and become concentrated.
- Add the mustard greens and a pinch of the salt. Stir well and cook for 2–3 minutes, until they begin to collapse.
- Add the Swiss chard leaves and another pinch of salt. Stir in ¾ cup of the water or vegetable stock and bring to a gentle simmer. Cook uncovered for 8–10 minutes, stirring occasionally, until the greens are tender and the mixture has become a thick, spoonable gravy. Add a little more liquid if it becomes too dry.
- Stir in the nasturtium leaves and cook for 1–2 minutes, just until wilted.
- Return the potatoes to the pan. Roughly mash a few of the potato pieces into the greens to help thicken the gravy, leaving most of the potatoes intact. Simmer gently for another 8–10 minutes, until the potatoes are completely tender and the flavors have come together.
- Stir in the garam masala and 1 Tbsp lime or lemon juice. Taste and adjust the salt and acidity, adding more citrus if needed. If the saag is too thick, add a splash of water or stock; it should be loose enough to spoon easily over rice, but not soupy.
- Serve hot, garnished with chopped cilantro and accompanied by lime wedges.
