1 Mix The Marinade Ingredients Together And Coat The Tuna Steaks With The Marinade, Cover Tightly, And Refrigerate For At Least An Hour. 2 Heat A Non-Stick Skillet Over Medium High To High Heat. When The Pan Is Hot, Remove The Tuna Steaks From The Marinade And Sear Them For A Minute To A Minute And A Half On Each Side ( Even A Little Longer If You Want The Tuna Less Rare Than Pictured.) 3 Remove From Pan And Slice Into 1/4-Inch Thick Slices. Sprinkle With A Few Green Onion Slices. Can Serve Plain, With White Rice, Or Over Lettuce Or Thinly Sliced Cabbage Or Fennel. Shown Served Over Sliced Fennel Salad.