Tartine's recipe takes the traditional lemon curd process and reverses it, not only saving time, but also producing something richer, silkier, and just better in the end.
A typical lemon curd starts with lemon juice, egg (yolks or a mix), sugar, and sometimes butter melted together and whisked over a double boiler until it thickens. It's delicious. Lemon meringue pie, pavlova, and trifle have been known to depend on it.
But Elisabeth Prueitt, Tartine Bakery's pastry chef and co-owner, holds off on adding the butter till after the other ingredients have gotten to know one another. And then she adds a lot of it, violently -- a technique inspired by Pierre Hermé. You'll see!
Naturally (this is an iconic pastry book, after all), there are specific temperatures involved, but I've made this with scalawag thermometers that couldn't be trusted, and just went by looks. It's very forgiving.
You just do that whisking-over-a-double boiler thing till it gets thick and glassy and leaves a lingering trail behind your whisk (or you can go rogue and cook it over low, direct heat -- just be prepared to strain out any cooked egg bits).
Then you pull it off the heat to cool while you slice your butter into neat tablespoons and pull out your blender.
Here comes the violence: You scrape the curd into the blender and let it rip, dropping in pats of butter one at a time. Each one is greeted with a satisfying -- suck! glurgle! -- as the lemon curd drinks up the butter and slowly swells.
The chunks of chilled butter cool down the mixture and thicken it faster than the traditional all-stovetop method would, while the blades of the blender beat in extra air.
The result is a buoyant, stable buttercream that stays spreadable in the fridge for days. It's smoother and more mellow than curd, which is often so severe in its pucker that you must take measures to lighten it after the fact -- a mousse folded in; a thick, sweet layer of meringue piled on top. You won't need, or want, to do that here.
Got a genius recipe to share -- from a classic cookbook, an online source, or anywhere, really? Please send it my way (and tell me what's so smart about it) at [email protected].
Photos by James Ransom
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I'm an ex-economist, ex-Californian who moved to New York to work in food media in 2007. Dodgy career choices aside, I can't help but apply the rational tendencies of my former life to things like: recipe tweaking, digging up obscure facts about pizza, and deciding how many pastries to put in my purse for "later."