https://cooking.nytimes.com/recipes/1019422-scarletts-tuna-salad
(adapted)
2-4 servings
INGREDIENTS
PICKLED ONION
½ cup rice-wine vinegar
½ cup hot water
1 tablespoon sugar
2 teaspoons kosher salt
1 red onion, peeled, halved and thinly sliced
SALAD
3 Persian cucumbers, peeled if skin is thick and waxy, sliced about 1/4-inch thick
2 spring onions, thinly sliced
2 limes, juiced, about 1/4 cup
5 to 7 ounces tuna (drained if canned; try fresh sushi grade tuna?)
1 avocado, peeled and cubed
GARNISH/FINISH
½ teaspoon or more flakey finishing salt
Freshly ground black pepper, to taste
Handful basil leaves, washed and torn
Handful cilantro sprigs, washed and torn
Handful fresh mint leaves, washed and torn
3 tablespoons extra-virgin olive oil
PREPARATION
Pickle the onion.
Boil water
In glass jar with lid, mix & shake to dissolve sugar: vinegar, sugar and 1 teaspoon kosher salt hot water.
Blanch onions for a few seconds, drain, add to pickling solution.
The pickled onions will be ready to use in an hour, or can be made ahead and kept in the fridge for up to a week.
Assemble salad.
In a large mixing bowl, dress cucumber and spring onions with lime juice and remaining kosher salt and It should be fairly wet. Pour into a deep serving plate or a wide bowl, along with any extra liquid at the bottom of the bowl.
Break or cut tuna into bite-size pieces, into mixing bowl.
Add avocado, 3 tablespoons of pickled red onion and 1 tablespoon of pickling liquid, and mix gently.
Scatter over cucumber mix
Garnish.