Measure out 1 cup of sugar in a bowl and set aside, close to where you'll be cooking the jam.
In a separate bowl, combine the 1 tbsp sugar with the 1/4 package (13 g) of pectin. Mix to blend well.
Combine the pectin/sugar mixture with the 1 cup of cooked fruit juice/pulp in the heavy duty saucepan.
Place that saucepan on a medium-high burner and heat the mixture to a rapid boil.
Boil for 1 minute.
Add the sugar, stir well.
Return to a rolling boil, stirring all the while.
Boil for 1 more minute.
Remove from heat immediately.
Pour into heatproof jars or freezer containers. This recipe almost fills 3 four-ounce jars, depending on high you fill them.
When cool, cap, label, and store in your fridge for 2 to 3 weeks, or freeze for about 6 months.