Step 1

Steam the sticky rice until tender (see Editor's Notes, below).

Step 2

Meanwhile, place the coconut milk in a heavy pot and heat over medium heat until hot. Do not boil. Add the sugar and salt and stir to dissolve completely.

Step 3

When the sticky rice is tender, turn it out into a bowl and pour 1 cup of the hot coconut milk over; reserve the rest. Stir to mix the liquid into the rice, then let stand for 20 minutes to an hour to allow the flavors to blend.

Step 4

Meanwhile, peel the mangoes. The mango pit is flat and you want to slice the mango flesh off the pit as cleanly as possible. One at a time, lay the mangoes on a narrow side on a cutting board and slice lengthwise about 1/2 inch from the center — your knife should cut just along the flat side of the pit; if it strikes the pit, shift over a fraction of an inch more until you can slice downward. Repeat on the other side of the pit, giving you two hemispherical pieces of mango. (The cook gets to snack on the stray bits of mango still clinging to the pit.) Lay each mango half flat and slice thinly crosswise.

Step 5

To serve individually, place an oval mound of sticky rice on each dessert plate and place a sliced half-mango decoratively beside it. Top with a sprig of mint or basil if you wish. Or, place the mango slices on a platter and pass it around, together with a serving bowl containing the rice, allowing guests to serve themselves. Stir the remaining sweetened coconut milk thoroughly, transfer to a small serving bowl or cruet, and pass it separately, with a spoon, so guests can spoon on extra as they wish.

Step 6

You can substitute black Thai sticky rice for half the white rice. Soak the two rices together; the white rice will turn a beautiful purple as it takes on color from the black rice. Cooking will take 10 minutes longer.

Step 7

Unlike plain sticky rice, Coconut Milk Sticky Rice has enough moisture and oils in it that it keeps well for 24 hours, in a covered container in the refrigerator, without drying out. Rewarm it the next day by steaming or in a microwave.