2Place potatoes into a large pot and cover with salted water; bring to a boil. Reduce heat to medium-low and simmer until tender, about 15 minutes. Drain and transfer potatoes to a large bowl. Mash potatoes with 1 tablespoon butter using a potato masher or fork; season with salt and pepper.
3Melt 1 tablespoon butter in a large skillet over medium heat. Cook and stir beef in the hot skillet until browned and crumbly, 5 to 7 minutes; drain and discard grease. Stir onion soup mix, chicken bouillon, and beef bouillon into ground beef; simmer until flavors blend, about 2 minutes. Add water if mixture is too dry.