Be sure to toast and skin the hazelnuts before adding them to the cream. Toasting brings out the rich flavor of the nuts and loosens the skins, which can taste bitter. Place the nuts in a dry fry pan over medium heat and toast, shaking the pan or stirring occasionally, until the nuts are fragrant, 10 to 15 minutes. Or spread the nuts in a single layer on a baking sheet and toast in a 325deg.F oven, stirring occasionally, for 10 to 15 minutes. While the nuts are still warm, wrap them in a kitchen towel and rub vigorously to remove the skins. It's OK if a few bits of skin still cling to the nuts.