Chicken tikka burgers

• 6 small chicken breasts
• 6 burger buns (we used ciabatta)

For the marinade

• 2 tbsp tomato purée
• 200g pot Greek yogurt
• thumb-sized piece ginger , very finely grated
• 4 garlic cloves , very finely grated or crushed
• 2 tbsp garam masala
• ½ tsp ground cinnamon
• ½ tsp ground cayenne pepper
• juice 1 lemon , plus wedges to serve

For the chutney

• 2 tomatoes , chopped
• 1 small red onion , chopped
• 1 green chilli , chopped
• 1 tsp tamarind pulp
• 2 tbsp tomato ketchup

For the salad

• ½ cucumber , sliced
• 1 Little Gem lettuce , shredded
• small bunch mint , leaves picked
• 1 small red onion , halved and finely sliced