@Sierra02 - I am a huge fan of seared ahi tuna myself but I have never tried to cook it at home. You got my curiosity up so I decided to do an Internet search and this is the closest thing I could find to it.
Two teaspoons of five-spice powder available at most grocers on the spice aisle.
One-half teaspoon of wasabi paste
One tablespoon of rice vinegar
One tablespoon of soy sauce
Three tablespoons of olive oil
Salt and pepper
Combine all the ingredients together and then chill until you're ready to serve. Like Kernel Sanders eleven herbs and spices, it must be a close guarded secret. Let us know how well it turns out.