To make the filling, chop and sweat the onion until softened in a little veg oil, add the garlic and ginger and cook for another 30 seconds. Add the garam masala, cumin and coriander and cook for a further minute.
Add the diced sweet potatoes and the drained chickpeas into the onion mixture and mix well
Stir in the readymade stock, tomatoes, coconut milk and sugar. Bring to the boil and simmer for about 10 minutes until the sweet potatoes are completely tender but still holding their shape.
Fold the spinach into the sweet potato mixture and cook for another couple of minutes until the spinach is cooked through and tender. The mixture should be nice and chunky at this point – any excess liquid should be reduced down. Remove from the heat and leave to cool completely (2 hours)
Cut the puff pastry sheet into quarters
Add the cold filling mix onto the puff pastry and moisten the edges. Fold over to form a sausage roll.
Crimp the sides and place on a baking sheet with baking parchment