One of the most important qualities a cook needs to have is flexibility—the willingness and capacity to change plans on a dime, whether by necessity or by pure inspiration. The other day, for example, I was walking into a supermarket in New York City with a shopping list for a simple bean salad I'd intended to make, when I spotted a tall pyramid of Ataúlfo mangoes. When I left the store, I didn't have beans in my bag. I had those mangoes, plus coconut milk and Thai glutinous rice. Just like that, I'd gone from a savory bean salad to a dessert of Thai coconut sticky rice with mango (khao niao mamuang), all because Ataúlfo season had struck.
If you don't know Ataúlfos, they're a Mexican mango variety that's become increasingly available in the States during its brief season, which runs roughly from March to July. They're smaller and slimmer than those large Tommy Atkins mangoes that are usually available, but, more importantly, they're sweeter, more fragrant and flavorful, and less fibrous.
When their season hits, one of the places you're certain to see them here in New York is on Thai restaurant menus, almost always as part of this sticky-rice dessert. Of course, in Thailand, they use other varieties of mango and not a Mexican one like the Ataúlfo, but here in the Western Hemisphere, the Ataúlfo makes a good stand-in. (The lackluster Tommy Atkins, however, does not—when it's the only mango at the market, this dessert disappears from menus.)
I'm not much of a dessert person, but khao niao mamuang is one I routinely go gaga for. It's plenty sweet, which will satisfy sugar fanatics, but for me, it scratches other itches. The glutinous sticky rice makes it a welcome opportunity to down some satisfyingly dense, starchy carbs, while the coconut milk and silky-sweet mango ratchet each other up, their tropical aromas cresting into a wave that momentarily sweeps me from my gray concrete city to a lush rain forest, full of squawking parrots and the sound of waterfalls. That's right, this dessert is an Herbal Essences commercial for your mouth.
Making it is easy. The first step is to collect your ingredients. Assuming you've already found the mangoes, the only other thing that might require a little searching is the rice. Thai sticky rice, which also goes by the names "glutinous" and "sweet" rice, is essential for this dish. Once cooked, it has a mochi-like sticky, chewy, tender texture (not entirely surprising, since mochi is made from a Japanese variety of sticky rice). Other somewhat sticky types of rice, like the short-grain varieties used in Japan, Korea, and Italy, will not work well as substitutes.
This type of Thai rice also requires a long soak in water—at least an hour and up to overnight—before it's drained and then steamed. The steaming is simple enough: Just line a steamer with cheesecloth or a clean dish towel, add the rice in an even layer, and let it steam over boiling water for about 20 minutes.
While the rice is cooking in the steamer, put some full-fat coconut milk in a saucepan, then stir in sugar and salt until they're dissolved. I've found that about three-quarters of a cup of sugar per 14-ounce can of coconut milk hits the sweetness spot for me, but this is something that can easily be adjusted to taste. Make sure to add a generous pinch of salt, since you want to taste it. A good salty–sweet interplay is what you're going for.
Then transfer the cooked rice to a mixing bowl and pour the coconut milk mixture all over. It'll seem like way too much liquid, but give it a good stir, cover the bowl, and let it stand at least 20 minutes. The rice will absorb the liquid fully, leaving each grain plump and coated in a sheen of coconut oil.
While it's sitting, add some fresh coconut milk to the saucepan, bring it to a simmer, and then work in a little cornstarch, making a slurry with the starch and a small amount of the coconut milk before adding it to the main pot to prevent lumps. Once again, a large pinch of salt goes in. As soon as it's thickened, I add sugar again and stir to dissolve.
This may seem like an inefficient process—why not make one master batch of sweetened coconut milk and then reserve some to thicken with starch?—but it's necessary. The second batch of coconut milk forms a thick, creamy sauce that's drizzled over the rice, and it's quite a bit less sweet and more salty than the first batch. The extra sugar in the first batch is there to help sweeten all the rice it gets mixed with.
You can hold the coconut rice for a couple of hours, easily. As soon as you're ready to serve it, mound some of the rice on plates, arrange sliced mango alongside, and drizzle that thickened sauce all over. Some toasted sesame seeds add a nutty accent.
To be honest, I haven't thought much about that bean salad I never ended up making. I'm pretty sure you won't think about whatever it was you'd been thinking of making, either, once you change your plans in favor of this.