Trim the steak of all fat, tendon, and silver skin. Dice the clean meat into small, uniform pieces.
In a mixing bowl, combine chopped steak, shallot, chives, parsley, capers, egg yolk, mustard, soy sauce, and furikake. Drizzle in a bit of olive oil, then season with salt, black pepper, and a squeeze of lime. Mix gently until fully incorporated.
Warm the corn taco briefly in a dry pan until pliable and aromatic.
Spoon the tartare mixture into the center of the taco.
Top with a pinch of micro cilantro and a generous spoonful of roe caviar.
Finish with a final squeeze of lime. Serve immediately.