These are a fabulous alternative to a sandwich. Smoked chicken breast works brilliantly but if you can’t get hold of it a plain cooked chicken breast will work just as well.
A note from Eatopic: To segment the grapefruit use a serrated knife to cut the top and bottom off the grapefruit then sit it flat on one end and use the knife to work top to bottom removing all the skin from the sides. Slide the knife along each of the membranes to remove each segment.
Squeeze the pith over a bowl to collect the juice.