Deep-fried cod fillet:
Season the cod fillets with salt and pepper and pat them dry on a kitchen towel. 
Put the sieved flower into a bowl, add the beer and stir until smooth. 
Add the egg yolks, oil and salt. 
Beat the egg white with a little sugar in another bowl until frothy. 
Fold the frothy egg into the batter. 
Dip the cod fillets into the flour and the beer batter one by one. 
Deep-fry at 170°C, until they are light brown. 
Drain on kitchen paper and season with salt.

Mushy peas:
Sweat the shallot in the butter and season with salt. 
Add the cream and cook until the shallot has softened. 
Blanch the spinach in boiling water and add to the onion cream and the frozen peas. 
Wait until heated. Finely grind in a thermo blender and run through a sieve. 
Season with pepper and salt.

Tartar sauce:
Make sure that all the ingredients are at room temperature. 
Place a sieve in a bowl and rub the hard-boiled egg yolks through the sieve with a wooden spoon. 
Mix the egg yolks with the salt, pepper, mustard and vinegar. 
Gradually add the oil and continue to stir gently. 
Season with lemon or gherkin juice. 
Finely chop the capers, gherkin and green herbs with a sharp knife. 
Finely chop the shallot. 
Mix the chopped ingredients with the mayonnaise.