fresh basil leaf, to garnish
150²µ/5½´Ç³ú celeriac, peeled and cut to 2½cm/1in cubes
1 clove garlic, finely chopped
½ red onion, roughly chopped
100²µ/3½´Ç³ú puy lentils
pinch dried chilli flakes
salt and freshly ground black pepper
1 tbsp olive oil
1 tbsp tomato purée
200ml/7fl oz hot chicken stock (vegetarians may substitute vegetable stock)