In a Dutch oven or heavy soup pot, melt the butter or bacon fat over medium-high heat. Season the beef generously with salt and pepper. Put the beef in the pan in a single layer; don’t stir for about 1-1/2 minutes. Then stir occasionally until the meat is well browned on all sides, about 5 minutes. With a slotted spoon, transfer the meat to a plate.
Reduce the heat to medium low, add the onion and garlic to the pot, and cook, stirring and scraping the bottom of the pot occasionally with a wooden spoon, until they’re softened, about 5 minutes. Add the wine, bring to a boil, and cook until the wine is reduced by about half, about 5 minutes. Add the broth, squash, turnip, wild rice, tomato paste, thyme, and bay leaf and bring to a boil over high heat. Add the beef and any accumulated juices, reduce the heat to medium low, cover, and simmer until the wild rice is soft and most of the grains have popped open and are tender, 40 to 60 minutes. (Check occasionally to be sure the soup isn't simmering too quickly or too slowly; it should be a moderate simmer.) Discard the bay leaf. Season the soup with salt and pepper to taste and serve garnished with the parsley.