- 3 1/2 lb. ripe strawberries, preferably local
- 5 1/2 cups sugar
- 2 Tbs. fresh lemon juice
Adapted from williams-sonoma.com
Rinse the strawberries in a colander and drain. Hull the strawberries.
In a ceramic or glass bowl, combine the strawberries and sugar. Cover with parchment paper and let stand at room temperature until the berries release their juices, about 2 hours.
Pour the strawberry mixture into a large, heavy nonreactive pot and set over low heat. Cook, stirring gently, until the sugar is dissolved. Bring to a simmer and then pour the mixture into a ceramic or glass bowl. Cover with parchment paper and refrigerate overnight.
The next day, prepare 5 to 7 half-pint canning jars by washing and then boiling them for 10 minutes to sterilize. Place 5 small plates in the freezer to use for testing the jam.
Combine the strawberry mixture and the lemon juice in a large, nonreactive pot and set over low heat. Slowly heat the jam, stirring constantly. Increase the heat to medium-high. Using a flat metal spoon, skim the foam off the jam while continuing to stir. Cook the jam for 12 to 15 minutes. If the fruit starts to stick or burn, reduce the heat to medium. The temperature on a thermometer should register 221°F.
As the strawberries begin to thicken and start to gel, reduce the heat to medium-low. Continue cooking the berries, stirring frequently, until the jam is very thick, 3 to 5 minutes.
Test if the jam is set: Drizzle a few drops of jam on a plate from the freezer. Wait 15 seconds and then run a finger through the jam. The jam should wrinkle slightly and have a thick consistency. If the jam is not set, return the pot to the heat for 1 to 2 minutes and test again.
When the jam is set, remove the pot from the heat and skim off any remaining foam. Ladle the jam into the prepared canning jars. Dip the lids in boiling water to sterilize. Wipe the rims clean and place the lids on the jars.
To heat-seal the jam, place the jars in a boiling-water bath and boil for 10 minutes to seal. Makes 5 to 7 half-pint jars.