- Start by making mashed potatoes. Bring potatoes to a boil in a large pot of water seasoned with salt until the potatoes are tender, about 20-25 minutes. Drain potatoes and return to warm pot. Add butter, salt, and garlic powder. Mash potatoes or whip with a hand mixer until potatoes are broken up. Add milk, sour cream, and chives. Mix until mostly smooth. Transfer potatoes to a large bowl and cover to keep warm.
- Heat 1 tablespoon of olive oil in a deep skillet or sauté pan over medium heat. Add sausage links and brown for 8-10 minutes until fully cooked. Set sausage aside on a plate.
- Add remaining oil and sliced onions to the drippings in the pan and sauté for 7-10 minutes, until softened and lightly browned.
- Reduce heat to low and whisk in flour. Slowly pour in 1 cup of beef stock as you whisk until flour and stock are well mixed. Add remaining beef stock, soy sauce, pepper and garlic powder and bring to a simmer. Simmer until gravy is thickened, whisking occasionally for about 5 minutes. Add sausage back to pan.
- Serve sausage and gravy with mashed potatoes.