In a large skillet, heat the olive oil over medium heat. Add the sausages and cook until browned on all sides, about 10 minutes. Remove the sausages from the skillet and set aside.
In the same skillet, add the sliced onions and cook until softened and caramelized, about 8-10 minutes. Stir in the minced garlic and cook for an additional minute.
Sprinkle the flour over the onions and garlic, stirring to combine. Cook for 1-2 minutes to eliminate the raw flour taste.
Gradually pour in the broth while stirring continuously to avoid lumps. Add the Worcestershire sauce and bring the mixture to a simmer.
Return the sausages to the skillet, cover, and let simmer for 15-20 minutes until the sausages are cooked through and the gravy has thickened. Season with salt and pepper to taste.
Serve hot, garnished with chopped parsley.