For each citrus fruit, be sure to wash and clean it well. Slice off both ends. For thinner, pithless (leatherlike) peels, use a veggie peeler and just cut off the external colored skin in 1/4 inch strips. For chewy peels best used chopped in baked breads and cookies, use a knife to score and peel by hand. Simply score each fruit into sections from end to end (attempt 1/4 inch strips). Use your fingers and peel off the rind (peel and pith) into strips (based on your scoring sections.) You can cut off more pith, if you choose. You can also cut the strips into narrower strips after you've peeled them off the fruit. Store the peeled fruits into sealed containers or bags in the fridge and use for anything else.
In a large saucepan, place all peelings and cover with water.
Bring to a boil and cook for 15 minutes. Boiling the peels helps to remove the bitter pith flavor.
After 15 minutes of boiling, pour the peels into a colander and drain over the sink. Rinse well and place them all back into the large saucepan. Repeat by covering with water, boiling for 15 minutes, draining, and rinsing. You will likely need to do this 2 times unless you use thinner strips without pith. If no pith, just boil, rinse, and drain once. Place the boiled, rinsed, and drained peels into a large bowl and set aside.
To the same large saucepan, add 1 cup of fresh water and 2 cups of sugar. Bring to a boil for a couple of minutes until the sugar has dissolved. Add the fruit peels and simmer for 15-20 minutes stirring occasionally to create a fruity syrup.
In a medium bowl or pan, add some sugar to coat the peels.
Use tongs to remove some of the peels from the syrup. Allow the syrup to drain off and then place them in the bowl of sugar. Toss to coat. Shake off any excess sugar and place the peels individually onto a cooling rack set over a cookie sheet (to allow for additional draining). Continue this process with all of the peelings adding more sugar as needed to coat.
You may find the peels to be sweet enough without the extra sugar coating. If so, skip the sugar coating step and place the peels from the syrup on the cooling racks over a cookie sheet to dry.
Leave the cooling racks over the cookie sheets on the counter. It will likely take 1-2 days to dry completely. Once the peels are dry, store them in a sealed container or bag at room temperature for a month. For prolonged freshness, store them in the fridge for a month or longer and in the freezer for a couple of months.