Crushing the berries jump-starts the release of pectin and decreases the cooking time, ensuring maximum fresh flavor.
Place metal spoon in freezer to chill. Combine strawberries, sugar, and lemon juice in large saucepan. Bring to boil over medium-high heat, then reduce heat to medium. Mash fruit with potato masher until fruit is mostly broken down. Simmer vigorously until fruit mixture thickens and spatula leaves trail that does not fill in immediately, 15 to 25 minutes.
To test for proper thickness, remove saucepan from heat. Dip chilled spoon into jam and allow jam to run off spoon; jam should slowly fall off spoon in one thickened clump. If jam is runny, return to medium heat and simmer for 2 to 4 minutes before retesting. Transfer jam to jar and let cool completely. Cover with tight-fitting lid and refrigerate for up to 3 weeks.
The Advantages of Refrigerator Jams
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