Was the citrus well and scrub them dry. Slice into ¼ inch thick rounds.
Place the orange slices in a pan with enough water to cover the slices. Bring it to a boil and simmer for 10 minutes. Remove the slices from the water and place in a ice water bath to stop cooking. Discard the cooking water.
Take 4 C water and 4 C sugar in sauce pan heat. Bring it to a boil stirring in between until all the sugar is dissolved. Add the orange slices.
Once the syrup is boiling again, reduce the heat to keep it on low boil. Keep it boiling for 20 to 25 minutes stirring once or twice. By this time the slices should look translucent. If not cook longer until it becomes translucent. (Notes)
Turn off the heat. Line a cookie sheet with parchment paper and place a cooling rack on it. Remove the slices from the syrup and place on a cooling rack. Let it dry on the cooling rack for 24 hours before using.
Once the slices have cooled for a couple of hours roll them in sugar if desired.
Store the granulated sugar-coated slices in airtight containers at room temperature for about a month. The slices can be frozen or refrigerated for longer storage. (Refer to the post for more details)
Any kind of citrus can be used in this recipe. The sugar syrup made is enough to cook 4 medium sized oranges.
20 - 25 minutes cooking time is enough for slices that are 1/4 inch thick. If making thicker slices increase the cooling time to 40 minutes or more.
For detailed instructions go to https://oventales.com/candied-orange-slices/ .