This is a nice side or addition to salad. The earthy mushrooms are brightened by a bit of vinegar and fresh herbs. I like this cold. If chilling, use avocado oil in place of butter.
Combine butter and olive oil In a medium pan and heat over medium heat. When warm, add the garlic and cook, stirring constantly until fragrant, about one minute. Do not brown. Add remaining ingredients except mushrooms and parsley. Bring to a boil then add mushrooms and simmer for 10-15 minutes, stirring occasionally. Add parsley off heat and serve.