Years before the flourless chocolate cake craze swept the United States, Lora Brody tasted a shockingly simple precursor in France—a gooey yet silky torte, richly intense with chocolate. Completely seduced, she was determined to recreate it back home, oblivious that asking for the recipe would change her life.

“The waiter disappears into the kitchen and comes back with some things written down,” she says. “But I thought, ‘There’s not enough ingredients.’” Butter, two kinds of chocolate, eggs, sugar, water and ... that was it.

The secret to this cake seemed as simple as the ingredient list, but appearances can deceive.

The chef told Brody the cake base is made by pouring hot sugar syrup over a mound of chocolate, which melts, then cools before being mixed with beaten eggs. Simple enough, except the ratios for getting just the right rich, creamy consistency proved elusive.

Sussing it out required more than a year of testing. She even reached out to Julia Child for an assist. In time, it came together: She eventually settled on a 9-inch cake pan, a syrup made from ½ cup water and 1⅓ cups sugar heated to 220°F, 12 ounces of bittersweet and dark chocolate, and 5 extra-large eggs. A friend named it bête noire—French for black beast—a double entendre as much about the difficulty of finding the correct proportions as about the cake’s death-­by-chocolate heft.

Brody published her recipe in The New York Times, a break that led to her “Growing Up on the Chocolate Diet,” the first of what would become 22 books.

It was the dessert’s hallmark simplicity, not to mention its clean chocolate flavor, that drew us in at Milk Street. But we saw ways to add complexity without altering the silky texture we loved. Instead of a simple sugar syrup, we made a caramel with black peppercorns and orange peel, then diluted it with orange juice and bourbon for a bit of balancing acidity. Two tablespoons of Angostura cocktail bitters offset the sweetness and reinforced the orange aroma.

The bittersweet orange-bourbon syrup was poured over the chocolate and butter through a strainer to capture the now-candied peel, which we coated with white sugar and reserved for an easy, elegant garnish. Once melted, the chocolate-butter mixture was combined with the beaten eggs, all of it going into a 9-inch parchment-lined springform pan.

Brody used a water bath to cook her cake, but we prefer the simplicity of lowering the temperature of the oven from 350°F to 275°F and adding 20 minutes to the cooking time.

Once the cake cooled, the sliced candied orange garnish highlighted the citrus in the chocolate, and the bourbon and bitters balanced the cake’s richness. But the silky texture remained, as did the intense chocolate flavor we wish we grew up with.