• Extract the Juice (skip if using bottled pear juice)
• Wash and quarter the pears. Don't peel or core; the peels and cores have most of the natural pectin.
• Place the quartered pears in a large saucepan with the water (about 1 cup of water per pound of fruit). Bring to a boil over high heat, then reduce heat, cover loosely, and simmer for about 30 minutes. Stir and crush the pears occasionally with a potato masher, just until softened. Don't overcook.
• Transfer the cooked pear mixture to a dampened jelly bag or strainer lined with several layers of dampened cheesecloth set over a deep bowl. Let drip undisturbed for at least 2 hours, or overnight for best yield. Don't squeeze the bag; squeezing releases solids that cloud the jelly. Measure out 4 cups of juice.
• Make the Jelly
• Prepare canning jars, lids, and water bath canner.
• Combine the pear juice and lemon juice in a heavy-bottomed jam pot. Whisk in the powdered pectin until fully dissolved. Bring to a hard rolling boil over high heat, stirring frequently.
• Add the sugar all at once and stir constantly until fully dissolved. Return to a hard rolling boil that can't be stirred down, and boil hard for exactly 1 minute.
• Remove from heat and quickly skim off any foam.

Can the Jelly

• Ladle the hot jelly into prepared half-pint jars, leaving 1/4 inch headspace. Wipe rims clean with a damp cloth and apply two-piece canning lids fingertip tight.
• Process jars in a boiling water bath canner for 10 minutes (15 minutes above 6,000 feet elevation).
• When the timer goes off, turn off the heat and let jars sit in the canner for 5 minutes before lifting them out.
• Cool on a towel for 12 to 24 hours, check seals, and refrigerate any unsealed jars. Sealed jars keep on the pantry shelf for up to 18 months.
Canning is optional. For Refrigerator or Freezer Storage: Let the filled jars cool to room temperature, then refrigerate (use within 3 to 4 weeks) or freeze in straight-sided freezer-safe jars (up to 6 months).