Drain the soaking liquid from the shiitake mushrooms and gently squeeze out the water from the mushrooms. Combine mushrooms with the sesame seeds, minced garlic and a pinch of salt and mix together. Coat a large skillet with the vegetable oil and heat over high heat. Add the seasoned mushrooms to the pan and stir fry for a minute or two, until the mushrooms begin to soften slightly. Remove from heat and stir in the sesame oil and green onion.