This recipe is so simple and divine, and leans heavily on the best quality ingredients you can get your hands on as it is so utterly simple.
Buy the best quality green tea soba noodles you can find, and boil in water for the specified time. The packets I normally buy are all in Japanese so I just keep an eye on them, about 6-10 minutes. If you hold your thumb and forefinger in a 3-4 cm diameter, this is the quantity of noodles per person. Rinse in cold water and dress with a little tamari and some of the crushed sesame seeds (gomasio) you will now make. Crush in a mortar and pestle a teaspoon of each of black and white sesame seeds for person with a little sea salt, e.g., 4 people, 4 teaspoons of each seed and lay in a dish so you can roll the tuna in them. Slice thick fillets of tuna into lengths so that they are long and almost square in shape. Roll each length in the sesame mix and then gently heat olive oil or coconut oil in a fry pan and sear each side for a minute or less depending on how happy you are with raw tuna, it should be VERY pink in the middle. Slice thinly and serve on the plate with the noodles and sliced cucumber.
Enjoy with a beautiful pot of genmaicha green tea.