Bring the prepared fruit and lemon juice to a low simmer in a large, covered saucepan. Cook until the fruit is very soft. Remove from the heat.
Run the cooked fruit through a sieve or food mill or blend with a blender/stick blender/food processor until smooth.
Return the puréed fruit to the saucepan, adding the liquid, sweetener, and seasoning of your choice.
Cook the fruit butter over medium-low heat until it stays spread apart with a spatula (anywhere from 30 minutes onward).
Decant the fruit butter into jars, leaving 1/4-inch headspace. Wipe the jars down and seal with two-piece canning lids until fingertip tight.
Process the jars in a water canner for 10 minutes.**** When the timer goes off, turn the canner off and let the jars sit in the very hot water for 5 minutes before carefully removing with a jar lifter.
Move the jars to a clean towel and let the fruit butter come to room temperature. Check the seal of each jar and remove the rings, unsealed jars should be moved to the fridge.
Store sealed jars of fruit butter in a cool, dry place for up to 18 months.