Cut the greens off of the beets, discarding the stems. Wash the leaves very well, spin dry and chop into 1-inch ribbons. Set aside.
Peel the beets. Slice each into 6 or 8 wedges, depending on their size. You want the wedges to be about 1 inch thick.
In a braising pan or Dutch oven, heat the butter and oil over medium heat. Add the curry powder and stir for a minute or so, until aromatic.
Add the onion and sauté until translucent and a bit softened, about 5 minutes.
Add the beet greens and cook until wilted, about 3 minutes.
Stir in the beet wedges and add the water. Bring it up to simmer, then cover the pot. Leave to braise until the beets are fork tender, about 25 minutes.