Fill a tall glass to the rim with pebble ice.

Pour the pineapple syrup over the ice so it pools before the soda is added.

Tilt the glass and pour the lemon-lime soda slowly down the inside wall, stopping when the foam climbs near the rim and settles.

Stir the coconut cream first in its own small container to loosen it, then pour it over the back of a spoon into the glass so it clouds rather than clumps.

Give one slow stir, hook the pineapple wedge onto the rim, and serve immediately.