In a medium saucepan, heat the oil over medium-high heat. Add the onions and cook, stirring frequently, until softened, about 6 minutes. Add the garlic and cook until aromatic, about 30 seconds. Stir in the flour until incorporated. Add the stock and bring the mixture to a boil, whisking constantly. Add the oregano and thyme. Reduce the heat to a simmer and cook for 10 minutes until thickened. Stir in the strained pan juices or apple juice and bring to a boil. Boil for 2 minutes. Whisk in the butter, salt and pepper until smooth. Pour into a pitcher and serve.