On medium heat, heat oil in a saucepan until hot. Add in hing, parsley, sesame seeds and allow to incorporate with oil for ~40-45 seconds, stirring occasionally. Toss in minced garlic, diced serrano chili and green onions, allow to simmer for ~30 seconds. Next add in bell peppers and mushrooms and allow to sauté for ~60 seconds. Pour in soy sauce and stir. Add siracha sauce, red pepper flakes and garlic powder. Mix all ingledients together.