In a bowl, prepare the sauce by combining the soy sauce, rice wine, sugar, sesame seeds & oil and garlic, reserve. PS: the smell of the sauce will paint your entire kitchen, it smells so good !!!
In another bowl, put the rice cake and cover it with warm(not hot) water. Let it soak 20-30 minutes then drain.
Heat a pan at medium-high heat, put some oil and add the rice cake. Stir so they dont stick, cover for 6 minutes. Add the onion and cook for a minute. Dump the sauce, the mushrooms and whichever vegetable you selected. Stir and cook for 2-3minutes
Serve and garnish with additional sesame seeds and/or green onions.