Heat oil in a large skillet over medium-high heat, then add onion and cook for 3 to 4 minutes or until translucent.Add mushrooms and cook for 10 to 12 minutes or until they release their liquid and become tender. Stir in garlic, rosemary and thyme and continue to cook for 1 minute until fragrant. Add wine and cook 1 minute, stirring constantly. Stir in broth and bring to a simmer.In a small bowl, whisk together soy sauce and tapioca flour to form a thick paste. Add mixture to the skillet, whisking constantly to make sure paste dissolves. Bring mixture to a boil and cook 2 minutes, stirring constantly. Add pepper and serve gravy hot.