Heat the oil in a large saucepan and saute the onion and green pepper for 3 minutes.
Add the garlic and ginger and stir for a minute. Add the chorizo sausage, aubergine and paprika and saute over high heat for 4 minutes.
Lower the heat to medium and cook until the aubergine is soft, about 3 minutes. Add the tomato paste and stir well.
Add the chopped tomatoes and stir. Pour in the stock, bring to the boil and simmer uncovered or half-covered until thickened, about 10 minutes.