There are no amounts because the ingredient list is from a Wellspring Grocery tuna salad bought to eat during one of Caroline’s Duke field hockey games in the late 1990’s. Normally ingredients are listed in order of amount, so that gives a clue that you should use more tuna than basil. No matter how you put it together, this is still good. You can leave out items you don’t have or don’t like.
canned solid white albacore tuna
(Wild Planet or American Tuna for sustainable fishing practices)
red or sweet onion