The flavor depends on the berries' being fully sweet, completely ripe yet firm, and with not a trace of white near the stem. Such berries have less pectin than ripe ones, so the jam will be loose.
Active time: 1 1/4 hr. Start to finish: 1 1/2 hr.
3 lb. ripe strawberries (4 1/2 pints), rinsed and hulled
4 cups sugar
1/3 cup fresh lemon juice
You will need 4 half-pint canning jars with lids.
Sterilize jars and lids.
Crush strawberries lightly with a potato masher in a 7- to 9-qt. heavy nonreactive (stainless steel) pot. Simmer, stirring occasionally, 10 minutes.
Add sugar and lemon juice and simmer, stirring constantly, until sugar is dissolved, about 2 minutes. Bring to a full boil and cook, stirring frequently (be careful not to let bottom scorch) and skimming off any foam. It’s done when it becomes slightly thickened and a teaspoon of jam begins to gel when dropped on a chilled plate, after 10 to 20 minutes of boiling. Ladle hot jam into jars, filling to within 1/4 inch of top. Wipe rims with a dampened cloth and seal with lids.
Put jars in a water-bath canner or on a rack set in a deep pot. Add enough hot water to cover jars by 2 inches and bring to a boil. Boil jars, covered, 15 minutes, and transfer with tongs to a rack. Cool completely and store in a cool, dark place.
"Its flavor depends on the berries' being fully sweet, completely ripe yet firm, and with not a trace of white near the stem. Such berries have less pectin than underripe ones, so the jam will be loose. Just spoon it out of a jar and dribble it on biscuits. "
Makes about 4 cups.