Sterilize canning jars. Place on a wire-rack set above a piece of aluminum foil, wax or parchment paper, or something to absorb any splashes from hot marmalade.

Prep the oranges before starting. First, peel. Scrape white pith from inside of the peel, as much as possible. Thinly slice the orange parts of the peel and set aside.

Then section fruit, saving juice and orange sections or segments in a bowl, while discarding the skin between each segment and any seeds you might find.

In a large, heavy-bottomed pot, combine orange peel, water and baking soda. Bring to a boil. Reduce heat to simmer and cover, simmering for 20 minutes. (While simmering, it's helpful to prep your workspace by opening pectin and setting in a glass next to the pot, ready to be added. You can also set a timer for 1-minute, ready to start the timer according to the directions below. Place ladle and funnel, if using, near canning jars. This stuff helps make the process go a bit smoother.)

After simmering for 20 minutes, add orange segments, cranberries, and cinnamon sticks. Return to a boil. Lower heat again, simmering covered for 10 minutes. If not already, start bring another large stockpot or canner (large enough so that jars will be covered with at least 2 inches of water) to a boil, for canning/processing.

Discard cinnamon sticks and add sugar. Stir constantly and bring to a full, rolling boil. Add pectin, continuing to stir. When the mixture once again reaches a rolling boil, start 1-minute timer. Continue stirring.

When timer goes off, quickly remove from heat and portion into prepared, sterilized jars, leaving a 1/4-inch headspace. Wipe rims clean and add lids. Screw bands on until just finger-tip tight.

Process in boiling-water for 5 minutes, with the 5 minutes beginning when water returns to a full boil. Remove from water and set on a wire rack to cool.