1. Bring a small pot of water to a boil with the bay leaf and boil the brain.

2. Hard boil the eggs.

3. Drain the brain, place it in a bowl and carefully mash it with a wooden spoon.

4. Mix the yolks into the mixture, soften everything with enough oil to obtain a homogeneous sauce.

5. Chop the spring onion, parsley, capers and add them to the sauce.

6. Season with lemon juice filtered through a sieve, adjusting the quantity according to your taste.