SERVES 4. HANDS-ON TIME 15 MIN, OVEN TIME 30 MIN
Heat the oven to 200°C/180°fan/gas 6. Cut 3 leeks (500g) into 8cm lengths, then wrap each in a piece of sliced, cooked ham from a 180g packet, cutting to fit and using up all the offcuts. Arrange in the base of a 1.5 litre ovenproof dish.
Meanwhile, melt 30g butter in a pan, then stir in 30g plain flour and cook over a medium heat for 2-3 minutes. Gradually whisk in 150ml dry white wine and 250ml milk. Bring to the boil, then simmer for 3 minutes.
Stir in 1 tbsp wholegrain mustard, 1 tsp chopped fresh thyme leaves and 75g grated cheddar until melted, then pour over the leeks. Top with 100g sliced brie, then bake for 30 minutes…