Peel, core and dice the pears into small pieces.

Toss the pears in the sugar and lemon juice. Place in an airtight container and refrigerate for 12 to 24 hours. If you’re short on time, reduce this step to a minimum of 4 hours but no less.

Prepare a water bath canner. Place the pear mixture into a heavy-bottomed saucepan and bring to a boil on high heat. Note that the mixture will foam, so choose a saucepan large enough to avoid spillage.

Stir the mixture occasionally, and cook for about 10-15 minutes. If needed, slightly crush any large pieces of pear with a potato masher.

When the preserves reach the gel stage, check the temperature with an instant-read thermometer. It should read 220°F at sea level and slightly below for higher elevations.

Immediately remove the preserves from the heat and pack them into mason jars with a ¼-inch headspace. Seal with 2-part canning lids.

Store the pear jam in the fridge for immediate use or process in a water bath canner for 5 minutes. Turn off the canner and allow the jars to sit for 5 minutes before removing them to a towel on the counter. Check for seals after a few hours and store any unsealed jars in the fridge.