Blueberry Port Wine Jam

Let's Cook

1. Step 1.

   Sterilize 6 or 7 pint-size jars with lids and bands by running them through the dishwasher. If you don't have a dishwasher, fill an 8-quart pot with water, place a rack or towel on the bottom, and bring to a boil over high heat. Add the jars, lids, and bands, turn off the heat, and let them sit in the water for about 15 minutes. Then place them on a towel-lined baking sheet to air dry.

2. Step 2.

   In a large bowl, combine 4 pounds fresh blueberries, 1½ cups sugar, and 1 cup port wine. Stir gently but well. Cover the bowl with a plastic bag or dish towel and let the fruit macerate for at least 2 hours, or up to 12 hours. This begins to break down the fruit and allows the wine flavor to soak in.

3. Step 3.

   In a heavy 8-quart pot over high heat, combine the macerated blueberries and any liquid, 1¼ cups honey, 2 medium plums (sliced), 1 teaspoon unsalted butter, and 1 tablespoon freshly squeezed lemon juice. Bring to a rolling boil, stirring frequently. Reduce the heat to medium-low to maintain a steady simmer. Continue to stir frequently, scraping the sides of the pot to prevent sticking. Let the mixture bubble for 45 to 50 minutes, until it reduces by almost half.

4. Step 4.

   To test for doneness, place a small plate or ramekin in the freezer for 5 minutes. Spoon a bit of the hot jam onto the cold plate and return it to the freezer for 1 minute. Push the jam with your finger; if it sets up and leaves a clean space, the jam is ready. Alternatively, check that the mixture has reduced by about half or that the temperature reaches 220°F.

5. Step 5.

   Fill the sterilized jars with the hot jam, leaving ¼ inch of headspace. Use a wide-mouth canning funnel for easy pouring. Wipe the rims with a clean, lint-free towel. Place the lids and bands on the jars, turning each band until secure but not overly tight.

6. Step 6.

   Place a canning rack or extra jar bands on the bottom of a large pot (8-quart pasta pot or 10- to 12-quart canning pot). Fill the pot two-thirds to three-fourths full with water and bring to a full boil. Using canning tongs, lower the jars into the water so they are fully immersed. Process for 10 minutes, then remove each jar to a towel on the counter and let cool. You will hear a 'plink' sound when a jar has sealed.