Pre-heat your oven to 220ºC/200ºC fan.
Place the lamb mince (500g), spices (1 tsp turmeric, 2 tsp hot chilli powder, 2 tsp ground coriander & 2 tsp ground cumin) and salt (¼ tsp) into a large bowl and use you hands to mix the spices into the mince until they are evenly distributed (I use a motion similar to kneading bread dough).
Divide the mince into 4 and then form into a burger shape. Make a dent in the middle of each burger (you'll find that they tend to puff up as they cook, making a dent in the centre means they'll end up looking flat once they're cooked).
Place onto a wire rack and then place the rack into a baking tray and cook for 12-15 minutes until hot all the way through.
While the burgers are cooking, make the cucumber raita. Grate the cucumber (150g) and use your hands to squeeze out any excess moisture.
Finely chop the mint leaves (I find this easiest to do with scissors).
Put the cucumber and mint into a bowl and add the yogurt (150g) and hot chilli powder (¼ tsp). Mix to fully combine, then season with a pinch of salt (add a little and taste before adding more if needed).
Once the burgers are cooked serve them in crusty rolls, with some salad and topped with the cucumber raita.