Add your peeled sweet potato chunks to a saucepan of water and bring to the boil. Boil for around 10 minutes until starting to soften, drain and set aside.
To a large frying on a medium to high heat add olive oil followed by your onion, garlic and ginger. Fry for 5 minutes until starting to soften.
Add all of your spices (curry powder, paprika, cinnamon and turmeric) along with your tomato puree, and mix so that the onion mixture is fully coated in all of the spices.
Add your chopped tomatoes and chickpeas and mix to combine. Add your veggie stock (starting with about half the stock and add more as and when you need it), salt and black pepper. Simmer for around 10 minutes.
Add your sweet potato, mix well and leave to simmer for another 15 minutes - or until the curry is nice and thick and the sweet potato is fully cooked. Add your spinach and stir until wilted.
Remove from the heat and add the lime juice. Serve with rice, coriander lime wedges and naan.