Making your own canned jam is definitely a Supermom Moment and with the holidays quickly approaching it would be a great neighbor or hostess gift to have handy. Using this easy self-sealing method, there is no special canning equipment required!
You’ll need about 4 pints of ripe strawberries. Begin by washing and hulling the berries. Then mash them up. Do not use a blender; for jam you want and uneven and chunky texture.
Before cooking the jam, make sure jars and sealing lids are totally clean — do a boiling water bath or wash them alone using the “sanitize” cycle on your dishwasher.
:: 4 cups mashed strawberries (about 4 pints fresh strawberries)
:: 7 cups sugar, in separate bowl
:: 1/2 teaspoon butter or margarine (optional)
:: 1 pouch liquid pectin (we used CERTO brand)
:: 4 pint-size glass jars
:: Matching metal sealing lids & rings
* It’s OK to double this recipe.
TO MAKE JAM: Measure exactly 4 cups of the mashed berries into a large pot. Stir in sugar and butter (to help reduce foaming). Bring mixture to a full boil that doesn’t go away when stirring. Stir in liquid pectin and return to a boil. Boil for exactly one minute, stirring constantly. Remove from heat. Skim off any foam. Carefully and quickly ladle into prepared jars. Wipe jars and threads clean then put on the metal sealing lids and tighten the screw rings.
TO SEAL: Invert the jars on the countertop and leave set for a few hours. As the jam cools, listen for the popping sounds of the lids sealing. Once jars are cool turn them right-side up and check the seal of each jar by pressing the lid — there should be no give. If the lids pops up and down then that jar did not seal. The jam in an unsealed jar is still good but must be refrigerated.