Summer prawn cocktail

2 eggs 1 large peach 250 g cherry tomatoes 1/3 cucumber 1+1 tbsp chives ((finely chopped)) 1+1 tbsp parsley (finely chopped) 100 g Greek yoghurt 2 tbsp mayonnaise 3 tbsp ketchup 250 g grey prawns 1/4 head of lettuce Salt and pepper