Wash, peel, core, and roughly chop the apples. You want to remove the skins and seeds while keeping the flesh.

Place the chopped apples in a large bowl and toss them with the lemon juice to prevent browning.

In a large pot or slow cooker, combine the chopped apples, granulated sugar, brown sugar, ground cinnamon, ground nutmeg, ground cloves, and salt.

Set the pot or slow cooker to low heat and let the mixture cook for 6 to 8 hours. Stir occasionally to prevent sticking and burning. The apples will release their juices and gradually turn into a thick and dark mixture.

Once the apples have cooked down and become very soft, use an immersion blender or a regular blender to puree the mixture until smooth. Be cautious as the mixture will be very hot.

Return the pureed mixture to the pot or slow cooker. Continue cooking on low heat, uncovered, for an additional 1 to 2 hours to thicken the apple butter. Stir occasionally.

Stir in the vanilla extract during the last 15 minutes of cooking for added flavor depth.

To test if the apple butter is ready, spoon a small amount onto a chilled plate. If it holds its shape and doesn't spread too much, it's done. If it's still too runny, continue cooking and testing periodically.

If you plan to store the apple butter for an extended period, you can can it in sterilized jars following proper canning procedures. This will make it shelf-stable.

Allow the apple butter to cool completely before transferring it to clean and dry jars or containers. Store in the refrigerator for up to several weeks or follow proper canning procedures for longer shelf life.