Begin by pureeing the strawberries and cranberries in a food processor; it does not matter if the berries are frozen or fresh, just puree either way; depending on the size of the food processor, this may have to be done in batches.
Transfer all of the pureed strawberries and cranberries to a large saucepan.
Measure the sugar and spices; add those to the saucepan as well.
Using medium-high heat, bring the mixture to a full boil.
Once fully boiling, meaning that even while stirring, the bubbles are still forming on top of the jam; continue to boil for one full minute.
Remove the saucepan from the heat source and add the liquid fruit pectin; stir well to combine and place the saucepan back on the heat.
Once the jam returns to a full boil, boil for one full minute, stirring the whole time; remove from the heat.
The bubbling will settle and once it does, use a spoon or ladle to skim off any foam and discard.
Ladle the hot jam into the jars being sure to leave 1/4-inch of headspace.
Place a clean, warm, sterilized seal on the jars and screw on a band until just finger-snug; that means that you should not apply any pressure when applying the screw band; just a snug fit is fine.
Lower the jars into the canning pot; be sure the water level covers the jars by two inches.
Bring the water to a boil; cover the canning pot and boil for 10 minutes.
Once done, remove the jars from the water and transfer to a heat-proof surface.
Allow jam to cool and set, undisturbed, for 12 hours.
Wipe jars and label accordingly; store jam in a cool, dark cabinet.