Tandoori lamb wrap

INGREDIENTS

• 150ml/5fl oz Greek-style yoghurt
• ½ small onion
• 1 garlic
• 2.5cm/1in piece fresh ginger
• 2 tsp each garam masala
• 1 tsp ground coriander
• ½ tsp ground fennel seeds
• ¼ tsp freshly ground black pepper
• 1 tbsp vegetable oil
• 2 tbsp fresh coriander
• ½ tsp red chilli powder
• 2 tsp lemon juice
• 1 tsp salt
• 400g/14oz lamb
• 2 tbsp melted butter
• 5 ready-made flour tortillas
• ½ onion
• 2 tomatoes, finely sliced
• 1 Little Gem lettuce
• 100ml/3½fl oz green chutney, mixed with 3 tbsp yoghurt
• You'll need ten wooden skewers, soaked in water for half an hour