Grapefruit With Campari Syrup

Directions

1. 1
   Cut peel, including all white pith, from 2 grapefruit with a sharp knife. Cut segments free from membranes, letting them fall into a medium-mesh sieve set over a bowl. Squeeze juice from membranes into sieve, then discard membranes. Transfer grapefruit segments to a heatproof bowl and chill, uncovered, while making syrup.
2. 2
   Squeeze juice from remaining grapefruit through sieve into bowl. Stir together 1 cup juice (reserve remainder for another use), 2 tablespoons sugar, and a pinch of salt in a nonreactive 10-inch heavy skillet and boil over moderately high heat, swirling skillet occasionally, until reduced to about 1/2 cup, about 4 minutes. Stir in Campari and sugar to taste, then immediately pour hot syrup over chilled grapefruit. Chill, uncovered, 15 minutes.