Mix soy sauce, rice vinegar, ketchup, sugar, black pepper, and water. Optional add in corn starch if you want a thicker sauce. Make sure to mix well
In a pan, turn the heat to medium-high and add in oil, and once the pan is hot, add in mushrooms and garlic.
Saute for 4-5 minutes or until slightly golden brown.
Pour in the sauce, mix well, cover and let it cook for 2-3 minutes or until the sauce has reduced to thicken.
Garnish with chopped green onions and sesame seeds, and enjoy!
