Quarter each orange. Remove peel and slice peel into thin slices. About a quarter inch in length.
Put slices in a sauce pan and cover in cold water. Bring cold water to a boil and remove the orange peels immediately from heat as soon as water hits a boil. Let the peels cool completely. (Repeat this process 2 or three times, until peels loose their stiffness and become more spongy.)
Remove any excess pulp from peels.
Place peels back into the sauce pan over medium low heat , adding orange juice, 3 cups of sugar and vanilla extract. Stir until sugar dissolves
Simmer this mixture for about an hour. Stirring occasionally.
Drain peels from sauce pan.
Preheat oven to 250'F
Put remaining 3 cups of sugar in a mixing bowl and toss the orange peels until they are completely covered.
Transfer the peels to a cookie sheet.
Bake for about 5-10 minutes, or until orange peel becomes slightly translucent.
Side note: if you allow the peels to dry coated in the sugar they make a good candied orange peel treat. Or you can bake like I did and you get a nice sugary gummy peel that goes good in ice cream, or stuffed in cakes or dipped in chocolate!!!