Original recipe from Real Good Fish, by Kevin Butler.

INGREDIENTS

1 lb ridgeback prawn tails
8 limes
1 jalapeño, seeded, diced 1/8"
1 serrano, seeded, diced 1/8"
1 onion, diced 1/4"
1/2 cucumber, seeded, diced 1/4"
1 roma tomato, seeded, diced 1/4"
2-3 sprigs cilantro
1 champagne mango (also called Ataulfo), diced 1/2"
1 orange
salt and pepper

DIRECTIONS

Blanch prawn tails in boiling water for 1 minute, then ice bath.
Once cold, peel tails and cut into 1/2 inch chunks. 
Zest 2 limes and reserve.
Juice limes into bowl with prawn meat. 
Cover and chill 4 hours or overnight.
Add onion, cucumber, tomato and mango.
Add chopped cilantro and lime zest.
Balance acidity with fresh orange juice.
Salt and pepper to taste.