For the ceviche, place the thinly sliced sea bass onto a serving plate and sprinkle over the lime zest, then drizzle over the lime juice, olive oil, and season with salt and freshly ground black pepper. Cover and leave to marinate for ten minutes (no longer) in the fridge.
For the lime and mango salsa, mix all the ingredients together in a bowl and then transfer to a small serving dish.
To serve, transfer the marinated sea bass onto a serving plate and serve with the salsa.
