Candied Citrus Peel

Preparation

1. Step 1

   Quarter fruit lengthwise and remove peel (including white pith) in 1 piece from each quarter, reserving fruit for another use.

   Step 2

   Cut peel lengthwise into 1/3-inch-wide strips (if using grapefruit, cut peel in half crosswise first). Put peel in a large bowl and cover with cold water, then soak 1 hour. Drain in a colander.

2. Blanch peel:

   Step 3

   Transfer peel to a wide 4- to 6-quart heavy pot. Add cold water to cover by 1 inch and bring to a boil. Reduce heat and simmer 10 minutes, then drain in colander. Repeat blanching process 2 more times. Cover peel once more with cold water and simmer until skin side is tender, about 30 minutes, then drain in colander.

3. Cook peel in syrup:

   Step 4

   Return pot to stovetop and add 6 cups sugar and 6 cups water. Bring to a boil, stirring until sugar is dissolved. Wash down any sugar crystals clinging to side of pot with a pastry brush dipped in cold water. Add food coloring (if using) and boil syrup, uncovered and undisturbed, until it registers 220°F on thermometer, about 30 minutes. Add peel and simmer over low heat until translucent, about 45 minutes. Remove from heat and let peel stand in syrup, uncovered, at room temperature 8 to 12 hours.

   Step 5

   Return syrup with peel to a boil and boil, uncovered and undisturbed, until it registers 226°F on thermometer, about 30 minutes. Remove from heat and let peel stand in syrup, uncovered, at room temperature 8 to 12 hours.

   Step 6

   Return syrup to a boil once more and boil, uncovered and undisturbed, until it registers 228°F on thermometer, about 30 minutes. Remove from heat and let peel stand in syrup, uncovered, at room temperature 8 to 12 hours.

4. Dry and coat peel:

   Step 7

   Reheat syrup with peel over low heat just until syrup has liquefied (peel will have absorbed most of syrup), then drain peel in colander. Immediately spread peel, separating pieces, on 2 metal racks set in 2 shallow baking pans and dry, uncovered, until just barely sticky, 8 to 24 hours.

   Step 8

   Spread 1/2 cup of remaining sugar on a plate and roll each piece of peel in sugar to coat well, then transfer to a sheet of wax paper. Add more sugar as needed to coat remaining peel. (Pour sugar through a medium-mesh sieve occasionally to remove bits of peel and clumps of sugar.) Dry sugared peel on wax paper 1 hour.