"Perfectly whipped cream has a smooth sheen like white, shiny frosting and will hold its shape, but no sharp peaks. Cream must be very cold to whip properly, and it is important to chill the bowl and whisk as well. This is because whipped cream separates very easily and even a little heat enhances the problem.
Cream should be whipped no more than a few hours before use, because it absorbs flavor from all the pungent things that are in your refrigerator. If you must whip in advance, underwhip it slightly, cover it well, and refrigerate until needed. Just before serving, remove it from the refrigerator and whisk it briefly before serving to bring out the full body.
The addition of a little sour cream or creme fraiche to every cup of whipping cream will ensure that beautiful sheen, extra smoothness, and fuller flavor." - Nancy Silverton
Note: You may sweeten this to taste if you like, with a few tablespoons of confectioners' sugar, which will also help stabilize the cream (due to the cornstarch). —Genius Recipes
crème fraîche (or sour cream), to taste
To whip by hand, you need a very large bowl and a large, balloon-style whisk. The large bowl is necessary to be able to whip the cream vigorously without making a mess, and the style of whisk is very important: If you whisk is too small or has too few wires, it will take much more effort to whip the cream. Whisking vigorously, it should take about 3 to 5 minutes to bring the liquid cream to the proper consistency.
By machine, start on low speed until the cream thickens enough not to spatter. Increase the speed to medium high and continue to whip, stopping the machine before the cream will hold soft peaks. Remove the bowl from the electric mixer and finish whipping the cream by hand with a whisk. Fold or gently whisk in creme fraiche.
Note: Salvaging extremely overwhipped cream can be done. You must add up to 1/4 cup of cold whipping cream and work it in, stirring with a rubber spatula to restore the proper consistency.