Start by placing any apple peelings and cores that you have in a large stockpot or saucepan. Fill the pot the rest of the way with water until the water covers the peelings. Turn the burner on to medium/high heat and simmer the mixture.

Let the peelings cook in the water until the cores become mushy and soft.

Place another stockpot or bowl under a strainer and place a piece of cheesecloth in the strainer to catch any smaller pieces. Pour the entire mixture through the strainer so you are just left with the liquid.

Place the liquid back on the burner on high heat. Add in the sugar. You will need roughly 4 to 5 cups of sugar for every 10 cups of liquid.

Continue to heat and bring to a boil. Using the candy thermometer, heat up the liquid until it reaches 218 degrees. Once at this temperature, let the mixture boil until it begins to thicken and form a syrup.

Pour the syrup into clean jelly or pint jars. Leave at least 1/2 inch of headspace in the jars.

Clean off the rims of the jars and place new lids and clean rims on tightly. Process the jars in a hot water bath for 20 minutes. Remove the jars when finished and let them cool undisturbed until the lids have sealed.