PARIS — Saturday, 7 p.m.

Oh no. I just realized I completely forgot about the upcoming bake sale at my kid's school.

Fast forward one hour, and the kitchen is a complete mess, with half a rushed moelleux sticking to the bottom of a pan. "But Mommy, no one'll want to buy that!" Never you mind: Tomorrow, Mommy will be taking part in a baking class with French pastry master Pierre Hermé — Tuesday's bake sale is taken care of!

On Sunday, once inside the kitchens of the Royal Monceau-Raffles Paris, where Hermé is the head pastry chef, I start getting butterflies in my stomach as I put on the pretty gray apron monogrammed "PH." On the menu, no yogurt cake (my go-to recipe), but a tarte infiniment vanille, or "infinitely vanilla-y tarte." Elisabeth Geoffroy, the chef's assistant, distributes the recipe. Seven steps?! And technical terminology I've only heard on Le Meilleur Pâtissier, the French TV baking competition: "Gently whisk the mascarpone, then loosen it gradually." Panic sets in.

Chief Pierre Hermé and his assistant Elisabeth Geoffroy — Photo: Le Monde

The chef walks in and asks around, "Has anyone made this recipe before?" A culinary journalist replies, "Not as a whole, no, but I know some steps, like the ganache." What a show-off.

One thing's for sure, I'm going to make a fool out of myself. Hermé passes three jars around, containing vanilla pods. "For this tarte," he says, "I wanted to create my own flavor of vanilla. I tried a dozen different types, before assembling three cultivars." And their aromas are indeed very specific. "This one from Tahiti is exuberant — I wanted that as a base note; this one from Madagascar is more woody, and this one from Mexico, more floral."

Time for the pâte sablée. Lo and behold, Geoffroy brings out circles of dough, ready for us to use: "In a one-hour class, we don't have enough time to go through all the steps, so I've already prepared the dough." Thank God.

Hermé takes the small circles, and shows us how to "line" the dough and remove the excess: "Careful, you don't want to pinch the dough, or the tarte won't have the same thickness everywhere and won't cook evenly! Don't worry, you'll get the hang of it." I try my best, but I'm having a hard time.

Our mission, should we choose to accept it: fill the tarte crusts.

And away they go, in the oven for 25 minutes, "with dry beans to prevent the dough from rising. There is nothing better! Metal baking beads tend to squish the dough." Oui, chef.

"It's crazy, it's like being on a TV program!" says one of the participants, as Geoffroy produces a tray of tartes ... once again, already cooked. Hermé takes a bite into one: "It's good, eh? Ha, looks like we've lost Elisabeth again ..." She comes back, this time with piping bags full of vanilla ganache. "Now, this is very easy," the pastry chef announces. "You melt the white chocolate in a bain-marie, scrape the vanilla pods, then boil the cream and mix everything together." Sure thing.

Our mission, should we choose to accept it: fill the tarte crusts. Oops, looks like I've opened my piping bag too much and now there's ganache all over my work space. Hermé pops by and dips his finger in the mess. "Do you always taste what you make?," I ask. "Unfortunately, I can't help myself," he replies, patting his stomach. "But of course, tasting is crucial." I follow his lead and try a spoonful of ganache. Delicious.

The last step is the trickiest one: enrobing the mascarpone disks with vanilla icing — Photo: Le Monde

The assistant then shows us how to moisten the sponge biscuit in a rum-and-vanilla-infused syrup (I taste it, too — hic!) and lay it on the bottom of the tarte. Then add a bit more ganache before heading to the fridge so it gets nice and firm.

Next and final trick, disks of vanilla mascarpone cream magically appear from the freezer. "When you make this at home, no need to freeze the cream, just spread it directly on top of the chilled ganache," says Hermé. Not sure I'll be able to replicate this recipe at home … Especially since the last step is tricky: enrobe the disks with vanilla icing so that it shines. "Voilà, very good!" the pastry chef tells me. So I do have a talent, as it turns out: icing.

One final dusting of vanilla powder using a tea infuser ball ("clever, eh?") and Hermé's signature tarte is ready for us to dig in. "Aren't you going to have a taste?" "Erm, no, I think I'm going to bring them home with me." Or rather, bring them to school, and — for once — be the star of my kid's bake sale.

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