Fill a 16-ounce glass to the rim with pebble ice.

Pour the coconut syrup directly over the ice so it pools at the bottom before anything else goes in.

Squeeze the lime juice over the ice and drop the spent half in.

Tilt the glass and pour the cola slowly down the inside wall, stopping when the foam climbs to about an inch below the rim and settles back down on its own.

Pour the half-and-half over the back of a spoon held just above the surface, so it spreads into pale, cloudy ribbons instead of sinking flat to the bottom.

Give the drink one slow stir with a straw, just enough to pull the cream through without flattening the fizz, then hang the lime wheel on the rim and serve right away.