In a heavy saucepan over high heat, combine the shallots, wine, and lemon juice. Boil the mixture until it is thick and syrupy. This will take between 10 and 15 minutes.
Reduce the heat to very low, and add the cream, salt, and pepper. Whisk in the cubed butter, a little at a time.
When the butter is fully combined and the mixture is emulsified, remove it from the heat.
Serve the sauce immediately