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Tuna melt with ketchup

Prep time
20 mins
Cooking Time
5 mins


msc ecolabel landscape

Tuna melt

  • One 6-ounce (160 g) tin of tuna (preferred pole & line caught and MSC certified) in sunflower oil, drained
  • 1 small red onion, diced
  • 1 spring onion, white and light green parts, finely chopped
  • ¼ bunch of flat-leaf parsley, leaves only, coarsely chopped
  • 3 tablespoons mayonnaise
  • Tabasco sauce
  • 4 slices of bread, preferably rustic
  • 1½ tablespoon (20 g) butter
  • 4 slices of cheddar cheese
  • Salt and pepper, to taste


  • 2 tablespoons olive oil
  • 1 garlic clove, minced
  • 1 small red onion, diced
  • One 14-ounce (400 g) can peeled plum tomatoes
  • 1½ tablespoon tomato purée
  • 1 tablespoon dark brown sugar
  • 1 tablespoon red wine vinegar
  • Salt and pepper, to taste


  1. Mix the tuna, onion, scallion, parsley, mayonnaise, and a few drops of tabasco in a bowl. Season with salt and pepper. Set aside.

  2. To prepare the ketchup: Heat the olive oil in a saucepan over medium-high heat and sauté the garlic and onion until soft but not browned, about 2 to 3 minutes, stirring frequently. Add the peeled tomatoes, tomato purée, sugar, and vinegar. Cook over low heat until thickened, about 3 to 5 minutes. Season the ketchup with salt and pepper. Press the sauce through a fine sieve and leave to cool.

  3. Butter each slice of bread on one side and turn over. Pile the tuna mixture onto the non-buttered sides of two slices of bread and top with the cheddar. Cover with the other two slices (buttered side up).

  4. Bake the toasted sandwiches for 2 to 3 minutes on each side in a dry frying pan over medium heat until the bread is crunchy and the cheese has melted.

  5. Cut the tuna melt diagonally and serve with the ketchup. 
Recipe from The Tinned Fish Cookbook: Easy-to-Make Meals from Ocean to Plate—Sustainably Canned, 100% Delicious © Bart van Olphen 2019, 2020. Translation © The Experiment, 2020. Reprinted by permission of The Experiment. Available wherever books are sold. 

Photo credit: David Loftus.

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