Heat the oil in a large saucepan. Add the capsicums, onion and garlic and cook gently for 5 minutes, stirring.
Add the stock, tomatoes and coriander. Cover and simmer for 30 minutes.
Purée the mixture in a blender. Return to the saucepan and heat through. Season to taste with salt and pepper, pour into serving bowls and swirl a little yoghurt on top.
Did you know?
*The longer a capsicum ripens, the sweeter and more nutritious it becomes. Red capsicums supply eight times the beta-carotene of green – and half again as much vitamin C. *Gram for gram, a red capsicum contains three times as much vitamin C as an orange.