1. Boil potatoes in salted water until tender, about 15 minutes. Drain, mash, and mix with milk and butter. Season with salt and pepper.
2. Heat olive oil in a skillet and cook chicken sausages over medium heat until browned and cooked through. Remove and set aside.
3. In the same skillet, sauté onions until caramelized, about 10-12 minutes. Sprinkle flour over the onions and stir.
4. Gradually add chicken broth and Worcestershire sauce, stirring to combine. Simmer for 5-7 minutes until thickened.
5. Return sausages to the skillet and coat with gravy.
6. Serve sausages and gravy over mashed potatoes, garnished with fresh parsley.