2 large or 3 small aubergines, sliced into 5mm/¼in rounds
1 bunch basil, chopped
2 garlic cloves, crushed
1 tsp Dijon mustard
1 x 400g tin chopped tomatoes
500ml/18fl oz passata
50²µ/1¾´Ç³ú plain flour
salt and freshly ground black pepper
2 tsp caster sugar
4 tbsp olive oil
50²µ/1¾´Ç³ú butter, plus extra for greasing
568ml/1 pint milk, warmed
100²µ/3½´Ç³ú Parmesan (or a similar vegetarian alternative), grated
6–7 sheets dried lasagne