This is one of those “what have we got in the cupboard/fridge?” meals, and there are a million variations. We had the world’s oldest sweet potato to use up, and a bunch of rather limp coriander, so this is what I made.
Peel and finely slice the onion. Gently fry until translucent. Add two or three cloves of crushed/chopped garlic, and about a thumb’s length of fresh ginger, either minced or grated. We keep a root in the freezer, which you can then peel very carefully with a very sharp knife and grate. Stir in the garlic and ginger along with about a tsp of ground coriander, and about 1/2 tsp each of chilli powder and cumin. Cook for a minute or two (gently) until the spices are fragrant.
Peel and dice the sweet potato. It’s going to cook in the sauce, so the pieces need to be quite small.
Add the tomatoes, drained chickpeas, sweet potatoes and enough water to make sure the liquid covers the spuds, and increase the heat. Once it’s bubbling, add the juice of half the lime, and about a handful of roughly chopped coriander. Reduce the heat to a simmer and cook until the sweet potatoes are cooked through. Add creamed coconut to taste (enough to thicken the sauce slightly), the rest of the lime juice and all the rest of the coriander, except for enough for garnish. Serve with naan or rice, and with the last of the coriander scattered over the top.