Blueberry Lemon Jam - lemons

Method

• Have ready four 8-ounce canning jars with 2-piece lids.
• Fill a large pot with water and bring to a boil over high heat, then decrease the heat so that the water is barely bubbling.
• Immerse the pint jars in the canning kettle.
• Place the rings and lids in a separate small saucepan and cover them with hot water.
• Leave the jars and lids immersed while you cook the jam.
• If you dont have a candy thermometer to tell you when the jam is done, place a small plate in the freezer.
• Combine the lemon slices, water, and 1/2 cup of the sugar in a large saucepan over medium-high heat; bring to a boil and cook undisturbed until the lemon slices are translucent, about 20 minutes.
• Add the remaining 3/4 cup sugar and the blueberries; cook, stirring occasionally, until the mixture thickens and reaches 220F on a candy thermometer, 20 to 30 minutes.
• If you dont have a candy thermometer, remove the plate from the freezer and immediately spoon a teaspoon of jam onto it.
• Let it sit for a few minutes until the jam cools, then tilt the plate and see how much it runs.
• It will probably not wrinkle and get firm the way jams with more pectin would, but it should be thick and only slightly run.
• If its too runny, continue cooking it down, stirring frequently, until it thickens further.
• While the jam is still hot, ladle it into the hot, sterilized canning jars, leaving about 1/4 inch of head space at the top.
• Remove any air bubbles by running a long, nonmetallic utensil, such as a chopstick or wooden skewer, between the jar and the jam.
• Top with the prepared lids, close tightly, and process for 5 minutes in a hot-water bath with the jars submerged by at least 1 to 2 inches of water.
• Remove from the water and let cool, undisturbed, to room temperature.
• Besides making that telltale ping when it seals, the lid of a properly sealed jar should be slightly concave and not move; if the lid springs down and back when you press your finger in the center, the lid is unsealed.
• If it doesnt seal, process it again or store it in the refrigerator instead of at room temperature.
• Store sealed jars in a cool, dry place.