Divide some green lettuce on the plates, place some lettuce beans and onion, and a dash of mayonnaise, you put the rest of the lettuce in a bowl and put on the table.
Cut the lemons in half and place them on the plate.
Cut the sludge tongues with a scissor, you cut tail from the bottom up in the opposite direction, pat them very well dry and season with salt and pepper.
Melt a large lump of butter in an anti -adhesive pan and fry the tongues in it on both sides nicely golden brown.
Fry the fries, place them on kitchen paper and place them at the table.
Divide the fish on the plates and serve immediately.