Bring broth to a boil, add beets, and set aside. Melt butter in a large skillet and saute the onion until soft. Add rice and cook another 5 minutes. Add wine or water, and vinegar, and stir until absorbed. Slowly add broth and beets to rice mixture, stirring until liquid is absorbed and rice is tender, about another 20 minutes. Season with salt and pepper. This is great with roasted meats.