For the baked red beets with chive cream, peel the beets and cut them into slices. Peel the onions as well and cut them into rings. Alternate layers of beets and onions in a baking dish.
Mix red wine with salt, pepper and mustard and pour over the beets. Cover the dish with aluminum foil and put it in the cold oven.
Turn the oven on to 200°C and let the red beets bake for about 1 hour.
In the meantime, finely chop the chives and mix with the cream. Season with salt and pepper.
Remove the finished red beets from the oven, arrange on plates and pour the chive cream over them.