Steps
1. Cut the skinless, boneless sea bass fillet into very small cubes, similar to tartare size.
2. Peel the avocado, remove the pit, and dice it into cubes matching the size of the sea bass.
3. Immediately toss the avocado cubes with the lemon juice to prevent browning.
4. In a deep bowl, whisk together the olive oil, remaining lemon juice, Dijon mustard, salt, and freshly ground black pepper until emulsified.
5. Add the chopped sea bass, avocado, finely chopped red onion, spring onion, and dill to the bowl with the sauce.
6. Gently mix all ingredients together carefully to avoid mashing the avocado and fish.
7. Drizzle a few extra drops of olive oil on top before serving.
8. Serve chilled as an elegant starter or light main dish.