How to Make It
Using a sharp paring knife, score the oranges lengthwise into quarters. Remove the peels and cut them lengthwise into 1/2-inch wide strips.
In a medium saucepan, cover the orange peels with water and bring to a boil over moderately high heat. Boil the orange peels for 5 minutes, then drain in a large colander. Repeat the blanching and draining process 2 more times to tenderize the orange peels and remove the bitterness.
In the saucepan, combine 2 cups of the sugar with the corn syrup and 1 cup of water. Bring to a boil over moderately high heat, occasionally washing down the side of the saucepan with a wet pastry brush. Add the orange peels to the syrup and cook, stirring occasionally, until the peels are somewhat transparent and most of the syrup has been absorbed, 40 to 50 minutes. During the last 10 minutes of cooking, stir frequently and watch carefully to prevent the peels from burning.
Spread 1 cup of the remaining sugar on each of 2 heavy, rimmed baking sheets. Drain the orange peels in a large colander. Using a fork or tongs, transfer each piece of orange peel to the sugar-coated baking sheets; do not clump the peels together. Let the orange peels cool for 15 minutes, then roll them in the sugar to coat completely. Let cool thoroughly in the sugar, then transfer the orange peels to a wire rack and let dry overnight. Discard the remaining sugar from the baking sheets.