How to make
Sprinkle the fish with plenty of salt, cut it into cubes; if canned, be careful not to over-salt it.
Allow to sit as is for two hours. If raw, then rinse well with cold water, dry it and soak it in the lemon juice. Keep it in a cool place for 30 minutes.
Strain the fish and add the lemon juice to the mustard, olive oil and paprika.
Combine the finely chopped core of the lettuce with the corn and beans, and pour the sauce on.
Add the fish and sprinkle it with paprika.