Creamy Hard Sauce

A hard sauce lightened with whipped cream, meant for hot steamed puddings. The only real technique is temperature control: everything must stay cold enough for the cream to hold, while the butter must be soft enough to cream smooth.

• Butter first, and thoroughlyThe sugar will not dissolve into cold butter, and any grittiness left at this stage stays in the finished sauce. Bring the butter to about 65F and beat it pale before any sugar goes in.
• 7/8 cup confectioners' sugarThat is one cup less two tablespoons, roughly 100 g. Sift it even if the box says it needs no sifting, as lumps will not break up once cream is folded in.
• The hot waterA quarter teaspoon is a very small quantity and reads oddly, but it is doing a real job: just enough moisture to loosen the creamed butter and sugar so the flavorings distribute. If the mixture still seizes, a few more drops will not harm it.
• "1/8 teaspoon lemon"Almost certainly lemon extract rather than juice: at this quantity juice would contribute a trace of acid and water rather than any perfume, and an eighth of a teaspoon is an extract measure.
• FoldingWhip the cream to soft peaks only, then fold it into the butter mixture in two or three additions with a spatula. Beating it in will deflate the sauce and can break the butter out as flecks.
• Chill, but not to stoneRefrigerate 30 minutes to an hour so it firms into a spoonable cream. Held overnight it sets hard from the butter and should sit out 15 minutes before serving.
• Yield and servingAbout 1 1/2 cups, enough for six to eight servings. Spoon it onto pudding, gingerbread or baked apples straight from the oven so it half melts on contact.