Have 4- or 5-250 mL jars and lids sterilized before hand. Keep the jars in a low heat oven and the lids in a small saucepan of simmering water.
Combine all the ingredients in a large, deep pot. Cook the jam on medium–high to first dissolve the sugar and then boil.
Skim the jam to remove foam as needed with a metal spoon. The jam will bubble up high in the pot and then eventually settle again. Continue cooking the jam until it reaches about 220ºF (the jam setting point).
Divide the jam among the jars, leaving a ¼ inch headspace. Remove air bubbles, wipe the rims clean, then cover with the lids, fingertight. If any of the jars aren't filled full, don't seal them. Instead you can cover them and enjoy them right away, storing in the fridge.
Seal the closed jars according to the manufacturers recommendations. I used Bernardin jars and I boiled my jam jars for 10 minutes to seal them.
Let sit 24 hours undisturbed before storing them in the pantry.