While getting jam ready for canning, begin heating water in canner, and prep jars, lids and rings per manufacturer instructions , so they're ready to go once jam is ready.

Place strawberries in large bowl and crush them (I use my potato masher to crush the fruit). You can use a food processor for this, but do not puree fruit. Use pulse button to chop fruit. You need small pieces of strawberries in the jam!

Measure exact amount of fruit the recipe calls for into large saucepot. Add fresh lemon juice and 1 box powdered pectin; stir to combine. (I add 1/2 teaspoon of butter also, which helps keep foam amount down during cooking.

Measure exact amount of sugar into separate bowl. Set aside.

Bring strawberry mixture to a FULL ROLLING BOIL on High heat. Stir mixture constantly (*A full rolling boil means the fruit doesn't stop boiling, even while stirring). As soon as mixture comes to a full rolling boil, dump ALL the sugar in at once, and stir well, to combine.

Bring jam back to a FULL ROLLING BOIL, then let it boil for 4 minutes. Be sure to stir jam constantly. When done, remove pan from heat. Skim off any foam on top of jam and discard.

Ladle hot jam quickly into clean, pre-heated jars. Fill each jar, leaving 1/8 inch of headspace. Remove air bubbles from jar by inserting a non-metallic utensil into jar 2 or 3 times. Wipe rims of jars with wet paper towel or dishcloth to remove any jam residue (residue prevents jars from sealing properly). Cover jars with prepared flat lid, add screwband and tighten. Place jars carefully (using canning tongs) onto canning rack. Lower rack into hot simmering water in canner. Make sure hot water completely covers jar tops by a couple inches (add additional hot water if needed). Cover the canner.

Bring water in canner to a gentle boil. Once boiling, process jam for 10 minutes.

When processing time is complete, remove jars and place them upright on a dish towel on counter until they've cooled completely (do not place hot jars directly onto kitchen counter. Temperature variances could cause jars to crack).

Once jars have completely cooled (12 hours or overnight), make sure to test seal on the jars before storing in pantry. (Press middle part of the lid with index finger. If it springs back, seal is bad, and jar will need to be stored in refrigerator). If jars have a good seal, label the jars and store in pantry.