I love to use crème fraîche because I don't like heavy-based sauces. It is rich and unctuous, but it's also incredibly light to cook with, almost disappearing into the air. It has a particular depth that enhances dishes, rather than obscuring them – it's irreplaceable.
1 tsp vegetable oil
1 onion, peeled and finely sliced
1 tsp coriander seeds
1 tsp fennel seeds
2 cloves garlic
4 fresh curry leaves
3 kaffir lime leaves
The juice of 1 lime
1 tbsp palm sugar or caster sugar
1 tbsp fish sauce
1 aubergine, cut into eighths
1 tin good-quality chopped tomatoes
1 tin coconut milk
120g/4oz of cooked white beans
1 small bunch coriander, stalks and roots finely chopped
80ml/3fl oz crème fraîche
Heat the oil in a frying pan. Add the onion. Grind the coriander and fennel seeds with a pestle and mortar and add to the pan. Cook for 5 minutes, then add the garlic, curry and lime leaves, lime juice, sugar and fish sauce.
Add the aubergine and cook for 10 minutes, then add the tomatoes and coconut milk and cook on a low heat for 15 minutes. Add the white beans and cook for a further 10 minutes. Spoon into a large bowl and serve with crème fraîche.