Wash blood oranges thoroughly.
Slice off and discard the ends of each orange.
Slice the rest of the fruit into quarter inch slices.
In a low and wide pot, combine sugar and water over high heat for the sugar to dissolve.
Once the sugar water begins to boil, add orange slices to pot for 20 minutes.
After 15 minutes, lower heat to medium and flip slices for another 20 minutes until the peels are translucent and the syrup has thickened.
Place a wire rack over a baking sheet, and transfer each slice to the rack to cool and harden. This process may take anywhere from an hour to overnight.
(Optional) Save the blood orange syrup in the refrigerator for other uses.
Adapted from these Candied Orange Slices.