01 - In a large heavy-bottomed pot, combine the chopped apples with lemon juice, apple cider, and water. Bring to a gentle simmer over medium heat. Cook for 10 minutes, stirring occasionally, until apples are softened.
02 - Lightly mash the softened apples with a potato masher or immersion blender, maintaining some small chunks for added texture.
03 - Add granulated sugar, brown sugar, cinnamon, nutmeg, allspice, and salt. Stir until the sugars are completely dissolved.
04 - Stir in the unsalted butter. Continue cooking over medium heat, stirring frequently, for 20 to 25 minutes. Mixture should thicken and take on a golden caramel color. Scrape the bottom of the pot regularly to prevent scorching.
05 - Increase the heat to bring the mixture to a rolling boil. Add the liquid pectin, stir thoroughly, and boil hard for 1 to 2 minutes. Remove the pot from heat.
06 - Remove and discard any foam. Carefully ladle the hot jam into sterilized canning jars, leaving a 1/4-inch headspace. Wipe the rims clean, apply lids, and process jars in a boiling water bath for 10 minutes, adjusting time for altitude as necessary.
07 - Allow jars to cool completely on a towel. Once cooled, store in a cool, dark environment. Refrigerate after opening.