Spinach, sweet potato and chickpea soup

Name: Spinach, sweet potato and chickpea soup
Cuisine: African
Ingredients: 2tsp olive oil; 1 onion, peeled and diced; 1 medium red pepper, cored, deseeded and chopped; 2 large carrots, peeled and diced; 2 garlic cloves, peeled and finely chopped; 1/4tsp ground allspice; ½ or 1 scotch bonnet chilli, deseeded and finely chopped – see Cook’s tip; 1 medium pink-fleshed sweet potatoes,peeled and cut into chunks; 1 tbsp fresh chopped thyme or 1tsp dried thyme; 1 litre vegetable stock, made usinglow-salt stock cubes; 400g can chopped tomatoes; 400g can chickpeas, rinsed and drained; 125g baby spinach leaves