This is a good way to use tangerines or "cuty" Clementine oranges. It works better to use thinner skinned fruit. I also use it as a filling for Czech kolache that are sweet yeast rolls. Tangerine marmalade is also good with oatmeal for breakfast. You can also sucralose (Splenda) or fructose for a lower glycemic index. Fructose or sucralose can be used for a lower glycemic index.
Rinse the seedless tangerines or Clementine oranges & slice them with peel on cutting board to chop up & chop up in food processor more.
Add 1 cup water & the chopped up tangerines & 4 cups sugar or fructose or sucralose (you can use fructose or sucralose for a lower glycemic index) & 1 teaspoon cinnamon & 1 teaspoon pure vanilla extract to a double boiler on a stove & cook for an hour under medium heat until dark orange in color & peel is cooked completely.
Put in jars with airtight lids or in a pyrex container with a lid & store in the refrigerator.