How to Make It
In a medium bowl, mix the papaya with the mango, red onion, tarragon, shallot, ginger and garlic.
Fill a large, high-sided skillet with 1/2 inch of water and bring to a simmer. Season both sides of the snapper fillets with salt and cayenne pepper. Add the fillets to the skillet, cover and simmer gently until just cooked through, about 7 minutes. Transfer the fish to plates with a slotted spatula.
Add the olive oil and lime juice to the papaya-mango mixture and season with salt and black pepper. Spoon the sauce over the snapper and serve.