It can be added anywhere. Until you know how creamy you want your beer, do it in the bottling bucket. Since I know how creamy I want mine, I added it to the boil.
Planning: Agave Witbock, Raisin Beer
Primary: GF Hazelnut Stout
Tertiary: Cranberry-Pom pLambic (est. bottle date: 03/01/08)
Drinking: Cab.Sav/Merlot Wine, Grand Cru, Hazelnut Stout #3, Ordinary Bitter