Chantilly cream
Chantilly is whipped cream with a little sugar, usually with vanilla. What separates it from plain whipped cream is exactly that sweetening and flavouring; the sugar is modest, typically 8–12% of the weight of the cream.
Only cream at 30% fat and above will whip, with 33–35% the practical optimum. Below that threshold there are not enough fat globules to build the network that traps air, and the cream stays liquid however long you whip it.
Everything should be cold: cream, bowl and whisk. Warm fat is pliable and forms no firm structure, so cream whipped in a warm room takes badly and collapses quickly.
Whip to soft or firm peaks depending on the job, but no further: past the peaks the fat network breaks, the cream turns grainy and eventually splits into butter and buttermilk. Split cream cannot be brought back, though it can be worked on into butter and used.