For the tahini yogurt, combine the ingredients with a splash of water, season well and mix until creamy. Spoon onto a serving plate.

Heat the oil in a large frying pan over a medium heat and cook the lemon slices in a single layer for 4-5 mins. Sprinkle in the sugar and cook for 3-4 mins more, stirring often until sticky and caramelised. Stir in the garlic, chilli flakes and prawns, and cook for 2-3 mins until the prawns are cooked through.

Spoon the prawns over the yogurt and serve with crackers or bread.