Heat the oil in a skillet over medium-high heat. Add the onion and sauté for 5 minutes or until softened. Add the mushrooms and sauté a further 5 minutes or until softened and browned.
Add the garlic and thyme and cook stirring for 2 minutes or until fragrant. Pour over the wine and allow to reduce for 2 minutes.
Season with salt and pepper then stir through parsley just before serving.