. Boil potatoes in salted water until tender, about 15-20 minutes. Drain, mash with butter and milk, and season with salt and pepper. Keep warm.
2. In a skillet over medium heat, cook chicken or beef sausages until browned and cooked through, about 10-12 minutes. Remove and set aside.
3. In the same skillet, melt butter and sauté onions with sugar until caramelized, about 10 minutes.
4. Sprinkle flour over the onions and cook for 1 minute. Gradually add broth and Worcestershire sauce, stirring constantly. Simmer until thickened.
5. Serve sausages over mashed potatoes, topped with onion gravy.