How to Make It
In a large saucepan, heat the olive oil. Add the onion and cook over moderate heat, stirring occasionally, until softened, about 6 minutes. Add the farro and cook for 1 minute, stirring to coat it with the oil. Add the wine and cook, stirring until it is absorbed, about 2 minutes.
Add the water, 1 cup at a time, and cook, stirring, until absorbed between additions. The farro is done when it is al dente and suspended in the thick, creamy liquid, about 25 minutes total.
Stir in the heavy cream, the cheese and butter and simmer until the risotto has thickened, about 5 minutes longer. Season with salt and pepper and serve.