How to Make Orange Marmalade

I am participating in the Food in Jars Mastery Challenge. 

I am looking forward to it. This recipe is from her blog: http://foodinjars.com/2017/01/small-batch-marmalade/

Ingredients

• 1 pound Seville oranges
• 4 cups water
• 2 cups granulated sugar
• 
  

Instructions

1. Give the oranges a good scrub and place them in a pot with a tight-fitting lid. Cover them with the water and set the pot on the stove over high heat. Bring the liquid to a boil, reduce the heat to medium-low, and put the lid on the pot.
2. Simmer the oranges for approximately 45-55 until the rinds are tender enough to be easily pierced with a fork. At this point, remove the pot from the heat and let the oranges cool completely.
3. When the oranges are cool, remove them from the pot. Measure out 2 cups of the cooking water and reserve it.
4. Cut the oranges in half across their mid-section, the way you would a grapefruit. Using a spoon, scoop the interior flesh out into a bowl. Remove the seeds and discard them. Put the seeded pulp into the bowl. Repeat with the remaining halves.
5. Once all the pulp is in the bowl, turn your attention to the rinds. Cut each half into 4 wedges and then cut those wedges into thin strips. These can also be added to the bowl.
6. Prepare a boiling water bath and 4 half pint jars.
7. In a saucepan, combine the reserved cooking water, the orange pulp, the zest ribbons, and sugar. Place the pot over high heat and bring to a boil. Cook at a controlled boil, stirring regularly for 20 to 25 minutes, until the volume in the pot has reduced by about half.
8. Monitor the temperature of the cooking fruit using an instant read thermometer. The marmalade is done when it reaches 220F. When it reaches that point, remove the pot from the heat.
9. Funnel the marmalade into the prepared jars, leaving 1/2 inch headspace. Wipe the rims, apply the lids and rings, and process in a boiling water bath canner for 10 minutes.
10. When the time is up, remove the jars and set them on a folded kitchen towel to cool. When the jars have cooled enough that you can comfortable handle them, check the seals. Sealed jars can be stored at room temperature for up to a year. Any unsealed jars should be refrigerated and used promptly.