Dulce de Leche-Stuffed Alfajores

The alfajor arrived in South America with Spanish colonizers, but it was transformed utterly in its new home. What began as a medieval Moorish confection of almonds and honey became something entirely different in the hands of Argentine and Uruguayan bakers: a delicate cornstarch cookie embracing caramelized milk. The European original is unrecognizable in its descendant. This is how the best culinary traditions work.

The secret to a proper alfajor lives in the cornstarch. Two parts cornstarch to one part flour creates a cookie so tender it threatens to dissolve before you can take a second bite. This is intentional. The texture should be barely there, a whisper of structure around the bold sweetness of dulce de leche. If you've only encountered these as dry, crumbly disappointments from a supermarket shelf, you haven't had a real alfajor.

I've watched home bakers overthink these cookies. They add flour because the dough seems too soft. They bake longer because the cookies don't brown. They fill sparingly because the dulce de leche seems excessive. Every one of these instincts is wrong. Trust the recipe. Trust the strangeness of it. The soft dough, the pale cookies, the generous filling: these are features, not flaws.

Make these for a holiday cookie exchange and watch them disappear first. Make them as a gift for someone who thinks they've tried every cookie. Make them because American baking has always been enriched by what we've adopted and adapted from everywhere else.