About 2 cups
In a medium bowl, add the drained tuna fish, mayonnaise, celery, shallot, lemon juice, pickle relish, a pinch of salt, and a few cracks of freshly ground black pepper.
Stir with a fork to combine, breaking up any large chunks of tuna fish as you go. Add more mayo if you'd like smoother, creamier tuna salad. Taste and adjust seasonings as needed.
Store in a covered container in the refrigerator for a few hours to let the flavors combine.