This recipe, modified just slightly from Ina Garten’s, cleverly employs 1/2 cup blueberries for added depth of flavor and color. The apple adds a natural source of pectin to help the jam will set.
3 pints fresh strawberries, washed and hulled
3 cups superfine sugar
2 tablespoons orange-flavored liqueur, such as Grand Marnier
1 Granny Smith apple, peeled, cored and small-diced
1/2 cup blueberries, fresh or frozen
1. Cut the larger berries in half or quarters and leave the small berries whole. Place the strawberries in a deep, sturdy pot such as a heavy Dutch oven or stock pot, and toss them with the sugar and liqueur.
2. If you plan to can the jam for long-term storage, place 6 1/2-pint jars in a large pot fitted with a wire rack, cover with water, and bring to a boil over high heat. Boil for 10 minutes.
3. In a saucepan, bring the lids and rings to a simmer.
4. Meanwhile, bring the berry mixture to a boil over medium heat, stirring often. Add the apple and blueberries and continue to keep the mixture at a rolling boil, stirring occasionally, until the jam reaches 220 degrees on a candy thermometer. This should take 25 to 35 minutes. Skim and discard any foam that rises to the top.
5. Remove the jars from the boiling water. Spoon the jam into the jars, leaving 1/4 inch headspace. You may not need all the jars. Wipe the rims of the jars with a damp paper towel. Place a lid on each jar, and screw down (not too tightly) with a ring.
6. Transfer the filled jars back into the pot of boiling water. When water returns to a full boil, boil for 10 minutes. Remove the jars from the water and place on a towel or cutting board to cool completely, without being disturbed, for several hours.
OR, if you do not plan to can the jam, allow the cooked mixture to cool to room temperature, then transfer it to a large jar or storage container, cover it, and store it in the refrigerator for up to 1 month.