Whether you like to use mayo or not, a good tuna salad requires all the ingredients to come together. A little umami will help balance the flavour, and these two fishy ingredients are perfect for the job. Photo by Vicky Wasik.
Sure, there's already fish in tuna salad, but Daniel Gritzer at Serious Eats recommends you up the fish quotient for a truly memorable dish. Add a healthy splash of Asian fish sauce or very finely minced anchovy and you'll get a satisfying savoury flavour, leaving any fishiness of the sauce to disappear into the tuna mixture. This trick will even work with canned tuna to boost its flavour. Some people add Worcestershire sauce, and that certainly helps with adding some umami, but you're better off with fish sauce or anchovies.