Heat a large saute pan over medium-high heat. Add the butter and the oil and cook, stirring, until the butter melts. Add the onion and saute 5 minutes, until soft and translucent. Add the shredded beets, 1 teaspoon of salt, and 1/2 teaspoon of pepper/ Saute about 10 minutes, until the beets are tender. Stir in the rice and cook 2 minutes, stirring constantly. Pour in 1 1/2 cups of the broth and water mixture, 3 teaspoons of vinegar, and 1 teaspoon of salt. Reduce heat to medium and simmer, stirring constantly, until the liquid has evaporated. Add 3/4 cup of broth at a time, stirring constantly and simmering until the rice is tender. Halfway through adding the liquid, stir in 1 more teaspoon of salt and 1/2 teaspoon of pepper. When the rice is almost ready, stir in the cream, 2 tablespoons of parsley, the last teaspoon of vinegar, 1/2 teaspoon of salt, and 1/4 teaspoon of pepper. Continue to cook, stirring, for another 2 minutes, or until al dente.