4cupsgranulated white sugarMeasure exactly. Crucial for a proper set.
1quartfresh strawberriesYields exactly 2 cups when crushed.
3ouncesliquid fruit pectinUsually one pouch of Certo (88ml).
2tablespoonsfresh lemon juiceBottled lemon juice also works perfectly.
Instructions
Wash the strawberries under cool running water. Pat them completely dry using a clean kitchen towel and remove the green leafy tops.
Crush the strawberries using a potato masher to a chunky consistency. Measure exactly 2 cups of the crushed fruit into a dry measuring cup, leveling it off perfectly.
Place the 2 cups of crushed strawberries into a large, microwave-safe bowl. Add the 4 cups of sugar and stir continuously for 1 minute.
Place the bowl in the microwave and heat on high power for exactly 3 minutes to melt the sugar crystals. Remove from the microwave and stir vigorously for 1 more minute.
Let the mixture sit on the counter for 2 hours, giving it a thorough 1-minute stir every 30 minutes. The mixture should lose its cloudiness and turn a deep crimson color. Taste to ensure no sugar grit remains.
In a small bowl, combine the fresh lemon juice and the entire pouch of liquid pectin. Pour this into the strawberry mixture and stir continuously for exactly 3 minutes.
Ladle the jam into clean glass jars or plastic freezer containers, leaving about half an inch of empty space at the top. Secure the lids tightly.
Leave the jars on the counter for 24 hours at room temperature to thicken and set. Store in the refrigerator for immediate use or freeze for up to a year.
Notes
Do not reduce the sugar or the jam will not set. If using frozen strawberries, thaw completely before crushing and do not drain the juices. Never substitute liquid pectin with powdered pectin for this recipe.