Drain the tuna really well by pressing down on the packed tuna with a fork, draining the can, and squeezing the daylights out of it.
Add the drained tuna to a medium size bowl and using that same fork, mix the lemon juice in with the tuna, breaking up any large pieces of tuna. Add in cayenne pepper and sea salt and stir to mix.
Add in mayonnaise, diced hard-boiled egg, pickle relish, celery, and 1 Tbsp. lemon juice in a medium bowl, until well combined. Season with fresh cracked pepper, and more sea salt and lemon juice, if desired.