Using a paring knife, score a circle on each citrus at the top and bottom of the fruit. Score down the citrus in 4 or 5 places, and remove the peel. Cut the peel into julienne strips.
Bring a small pot of water up to a boil and add the citrus peel. Let the peel boil for 1 minute, then drain away the water (this step draws out the bitterness from the peel).