Avocados turn tropical when paired with juicy grapefruit and lime.
Working over a bowl to catch the juices, use a paring knife to slice between the sections and membranes of the grapefruit; remove the segments whole. As you remove each segment, place it in bowl with juice. Bowl may be covered with plastic wrap and refrigerated for up to 1 day at this point.
Halve avocado lengthwise, and remove the pit. Arrange grapefruit segments in the center of each avocado. Drizzle with lime juice, and sprinkle with cilantro. Season with salt. Serve immediately with a spoon.