Clementine thumbprints add beams of sunshine to the year’s darkest days
Around this time each year, a giant box of clementine oranges takes up residence in my kitchen, where it is constantly replenished until sometime in mid-February. Clementines, satsumas, and other miniature orange varietals are just coming into season and are deeply associated with the winter holidays—I, like many others, always receive one in my Christmas stocking. To me, no other flavor embodies the holiday season quite like a clementine, yet for whatever reason, there are not many recipes that take full advantage of these perfumy little oranges. It turns out they make a beautiful, fragrant curd that tastes even better dolloped inside a buttery thumbprint cookie.
While you’re likely familiar with the classic lemon curd, I use clementine oranges instead for a floral depth of flavor. First, the sugar is rubbed together with finely grated zest, which releases fragrant oils and imparts major clementine flavor. The citrusy sugar is then whisked with egg yolks and cornstarch until smooth before juice is gradually added. A classic curd is thickened only with egg yolks, but adding a bit of cornstarch lends a smooth texture as well as some extra thickening power. It also helps prevent overcooking (curdling). While an ordinary curd would scramble before it ever began to bubble, this curd should be brought to a boil and whisked vigorously for about one minute to ensure that the starch gets fully cooked.
The cookie dough is fairly standard, employing both brown and granulated sugars for a texture that’s crispy on the outside and slightly soft within. It’s also lightly scented with clementine zest to echo the fragrant fruitiness of the curd. Unlike most cookie doughs, however, this one bakes up nicely from room temperature—no chilling required.
For the cleanest shape, I find it best to form the cookies into smooth balls, then bake them for five minutes before adding the “thumbprint.” Since the dough is hot, you won’t want to use your actual thumb here; I find the back of a half teaspoon measure makes the perfect hollow to fill with curd. Once filled, the cookies are returned to the oven to finish cooking. They’ll still look a bit pale when done. The exterior of the cookie should feel dry to the touch but still slightly soft beneath the surface—it will firm up once cooled.
My favorite thing about these cookies is that they bring a little bit of sunshine to the shortest days of the year by taking advantage of seasonal citrus. And they’re perfect not only as a holiday treat but also as a laid-back baking project for the early days of the new year. Any citrus would work well here—try something fun and seasonal like sumo oranges or tangerines. They’re only available for a limited time each year, so be sure to enjoy them while you can. In fact, I can’t think of a better excuse to make a batch of cookies.