Warm the oil in a pan over medium heat. Season the tuna with salt and brush it all over with 1/3 of the coconut aminos.
Cook the tuna for two to four minutes per side. This timing will depend on the thickness of the tuna and desired doneness.
Slice the tuna and divide it between lettuce leaves along with carrots, cucumbers, and cilantro.
Serve the lettuce bites with the remaining coconut aminos and enjoy!