In a small bowl, combine mayonnaise, mustard, relish and lemon juice. Mix well until ingredients are incorporated. Preheat the broiler and position the oven rack about 6 inches from the heat source. Spread each slice of toasted rye bread with the mayonnaise mixture. For each sandwich, top one half of the rye with 2 ounces keta candy fillets, then 1/3 cup sauerkraut, then 2 slices Swiss cheese. Transfer the four-layered halves on a small cookie sheet and place under the broiler just until the cheese melts. Remove from the broiler and top with remaining slices of bread.
A delightful twist to the Reuben sandwich, substituting Keta Candy for the corned beef. This sandwich provides a delicious and healthy on-the-go meal solution packed with omega-3 fatty acids.