(THE NEW YORK TIMES) - Here is an image that I can't shake: It's a Sunday afternoon. My husband Karl looks out the window of our first-floor West London flat; an expression of clear foreboding appears on his face and then, very quietly, he says: "Helen's here… with her cakes."
Helen Goh walks through our front door like a gust of wind or, rather, an overzealous dusting of icing sugar, carrying more cartons than humanly possible and, before even setting them down, begins apologising for all the things that went wrong with her cakes. This one hasn't risen properly, the other bowed around the centre, an icing has split during its application, a sabayon lost its air, a sorbet failed to churn, a sugar syrup crystallised, a cookie crumbled and so on.
Helen is an old friend and colleague who came to the Ottolenghi shops fresh off the proverbial boat from Australia, in 2006. I remember meeting for the first time outside one of our shops, big meringue piles looming above us. I heard her story, but couldn't quite understand what drives such a star to leave behind a successful career - Helen is a talented pastry chef and a successful psychotherapist - in a sunny Melbourne in favour of a rather elusive future in a rather grey London.
It took seeing Helen at work - first on the savoury side of the kitchen, then on the pastry side and, later still, spending much of her time dreaming up pastries, cakes and all manner of sweet things for the company - for the penny to drop. I finally realised that it was Helen's restlessness and her insatiable drive for perfection that had brought her to me.
What we shared was the notion that there is no upper limit to the number of times you can bake a cake or the amount of thought that can go into the components of a tart to get it just right; that you can discuss the minutiae of a chocolate ice cream or a nut brittle as if the fate of the entire universe rests on the conversation, without worrying for a second that this may be, just maybe, a tiny bit over the top.
Baking brought out our inner kids and, also, our inner geeks, with all the precise measuring, timing and weighing that informed all of our chats. The combination of the child whose enthusiasm never wanes and the nerd who won't rest until it's perfect led to some pretty sweet results.
Officially, she's a product developer for Ottolenghi, but that doesn't do her role justice; her originality and perfectionism have had an enormous impact on what we do. From Australia, she brought wonderfully crumbly and sharp yo-yo cookies, her billowy powder puff cakes that are just impossible to put down, and her chocolate cake, which is the cake grown-up kids dream of, and which a newspaper in Australia once called the world's best.
Her Malaysian heritage came through loudly in her chiffon cakes and pandan-infused pineapple tarts, which we often placed on the counter alongside our mince pies around Christmas. Her fluency in European and American baking traditions are everywhere - from the almond-and-aniseed nougat bars piled by the register to our cheesecakes and scones, which all sit beside the cakes I grew up eating, like the syrup-soaked semolina cake here.
Because I am a pastry chef and a notoriously sweet-toothed being with an insatiable appetite for cakes, my bond with Helen was immediate and firm. We spent the following decade conjuring up an enormous variety of sweet things. Eventually, all these led to Sweet, the cookbook Helen and I have been working on for the past three years, which is also my first book dedicated solely to sweets. The Sunday tastings at home were forerunners to our Wednesday tastings for the book, which happened in my test kitchen in Camden, North London. Similarly, they were long and intense - sugar being the fuel enabling us to carry on and the focus of our in-depth discussions.
Still, as much as we adhered to the old Sunday format, I must say that our capacity to consume sugar and abandon ourselves in cake conversation isn't quite what it used to be. I suspect it has to do with the fact that we both became parents in recent years. In our first meeting after Helen's son Sam was born, the three-week-old was resting in his Moses basket next to us while Helen and I were debating the merits of different consistencies of marshmallow for making s'mores. To my regret, I sent an offhand tweet reporting that an infant is the third wheel in our regular tastings, only to receive a bunch of grave warnings from concerned followers about the fatal risks of feeding cakes to newborns.
Children's birthday parties are now natural testing grounds for sponges and the boys are some of our fiercest critics. Just the other day, I offered four-year-old Max a slice of cake, to which he quickly replied: "Did Helen make it?"
"I am afraid not," I said.
"No, then," was his resolute and final answer. What a few years back may have been a very lengthy discussion was over before it had even started.
World's Best Chocolate Cake
For the cake:
1 cup plus 250g unsalted butter, at room temperature and cut into 2cm cubes, plus extra for greasing the pan
200g dark chocolate (70 per cent cocoa solids), chopped into 2cm pieces
1½ tsp instant coffee granules, dissolved in 350ml boiling water
2 large eggs, lightly beaten
2 tsp vanilla extract
1¾ cups plus 240g self-rising flour. If you cannot find self-rising flour, whisk together 1¾ cups plus 240g all-purpose flour and 2¾ tsp baking powder and use this mixture instead.
30g Dutch-processed cocoa powder, plus 1½ tsp, for dusting
¼ tsp salt
For the chocolate ganache (optional):
200g dark chocolate (70 per cent cocoa solids), broken or chopped roughly into 2cm pieces
180ml heavy cream
1 Tbs light corn syrup
1 Tbs unsalted butter, at room temperature
For the espresso cinnamon mascarpone cream (optional):
1½ cups plus 375 ml heavy cream
Scraped seeds of ½ vanilla pod
2½ tsp finely ground espresso
¾ tsp ground cinnamon
2½ Tbs powdered sugar
1. Heat the oven to 170 deg C. Grease a 23cm round springform pan with butter and line with parchment paper, then set aside.
2. Make the cake: Place butter, chocolate and hot coffee in a large heat-proof bowl and mix well until everything is melted, combined and smooth. Whisk in sugar by hand until dissolved. Add the eggs and vanilla extract and whisk again until thoroughly combined and smooth. Sift flour, cocoa powder and salt together into a bowl and then whisk this into the melted chocolate mixture.
3. Pour batter into the prepared pan and bake for one hour or until the cake is cooked and a skewer inserted into the centre comes out clean or with only a few dry crumbs attached. The top will form a crust and crack a little. Leave the cake to cool for 20 minutes before removing from the pan, then set aside until completely cool.
4. Make the chocolate ganache, if desired: Place chocolate pieces in a food processor, process until fine and set aside. Combine cream and corn syrup in a small pan and place over medium-high heat. As soon as bubbles begin to appear (just before it comes to a boil), remove from the heat. Get the food processor running again, with the chocolate still inside and pour in the hot cream in a steady stream. Process for 10 seconds, then add butter. Continue to process until mixture is shiny and smooth. (You can also make the ganache by hand; just make sure the chocolate is chopped fairly finely before adding the cream mixture. Stir with a wooden spoon until almost melted, then add the butter. Stir again until the ganache is smooth.)
5. Use a rubber spatula to scrape the ganache into a bowl and cover with plastic wrap, with the plastic touching the top of the ganache. Set aside until it has set to the consistency you want. If you want a thin layer to spread over the cake, it can be poured over while liquid so that you get an even, light and shiny coating. For a thicker ganache with a spreading consistency, leave it for about two hours at room temperature. (The ganache can be stored at room temperature, providing it is not too warm, for three days or kept in the fridge for up to two weeks. It can also be frozen, although it will lose a bit of its shine when defrosted.)
6. Make the espresso cinnamon mascarpone cream, if desired: Place all the ingredients in the bowl of an electric mixer fitted with the whisk attachment. Beat for one to two minutes, until soft peaks form.
7. Peel the parchment from the cake and discard. Transfer to a serving platter and spread the ganache, if using, on top of the cake. Slice into wedges, divide the cake among plates and, if using, spoon the mascarpone cream alongside. With or without icing, the cake will keep well for four to five days in an airtight container.