Chocolate Chantilly

Set up a cool water bath. Fill a large bowl with cold water — not ice water, which will chill the chocolate too fast.

Melt chocolate. Pour hot water over the chopped chocolate and stir to melt. Alternatively, combine water and chopped chocolate and microwave on medium power for a few minutes, stirring until smooth.

Cool and whisk. Set the bowl over the cold water bath. Whisk occasionally as the mixture cools to room temperature, then whisk continuously until it thickens and reaches an almost soft-peak stage — about the texture of thick yogurt. If it goes grainy, simply melt it down and start again.

Rest, then serve. Let it sit for a few minutes so the cocoa butter can finish crystallizing and the mousse firms up enough to scoop. Serve immediately, or refrigerate.