Balık ekmek, literally “fish-bread,” is what the Turks call these sandwiches. I’ve taken the concept and added some new flavors.
On an oiled griddle, cook an oily fish fillet, like Boston Mackeral or Bluefish, cooking on both sides till done. Meanwhile mix mayonnaise and a spicy sauce like Goya’s Aji Amarillo (3:1 ratio, I’d guess) and spread on toast. Place cooked fish on toast, add sorrel leaves or lettuce. A tomato slice will complete the sandwich, but don’t bother unless it’s perfectly ripe and tasty – you’ll just ruin the whole thing.