Tuna-sauced Onions: A Creamy and Flavorful Side Dish…

Tuna-sauced Onions, a delicious appetizer to serve cold or at room temperature spread on slices of bread. I made the onions with tonnata sauce using sweet and mild tasting Tropea onion, of course you can also use other red, white or golden onions as long as they are sweet and of good quality. The onions are first cooked in sweet and sour and then when they are cold they are topped with the tuna sauce, I recommend leaving them in the refrigerator for a few hours before eating them so they will be even more flavorful.

Ingredients for Tuna-sauced Onions :

  • 250 g (9 oz) Tropea red onions (or sweet red onions)
  • 2 tablespoons sugar
  • 50 ml (3 1/2 tablespoons) vinegar
  • Extra virgin olive oil, as needed
  • 100 ml (1/2 cup) water
  • 80 g (3 oz) canned tuna in oil, drained
  • 10 g (1/3 oz) capers
  • 2 tablespoons mayonnaise

How to make Tuna-sauced Onions:

  1. Peel the onions and chop them finely, preferably using a mandoline to get thin and even slices so they cook evenly.
  2. Pour the onion into a pan, add a drop of extra virgin olive oil, a tablespoon of sugar, the vinegar, and water. Put on the stove and cook the onion until it becomes soft.
  3. When it is becoming soft, add another tablespoon of sugar. If needed to soften and cook the onion further, add a few tablespoons of water.
  4. Continue cooking until the onion is very soft and well wilted, and there is no more liquid in the pan.
  5. When the onion is soft and dry, transfer it to a bowl and let it cool.
  6. Prepare the tonnata sauce: pour into the blender glass the capers, the tuna fish from which you have removed the oil, and the mayonnaise.
  7. Blend for a few seconds until you have a smooth sauce.
  8. Pour the tonnata sauce into the bowl of onion and mix well so that it is well incorporated.
  9. Cover the bowl with a lid or plastic wrap and let it sit in the refrigerator for a few hours before serving.

Bon Appetit!