caramel pear butter

my canner is getting a workout this year. i started with cherry almond jam, the moved into spiced plum butter with smitten kitchen's peach butter thrown in somewhere, and a few unmentionables that will show up around christmas time. it seems like every other weekend i've canned something. now that it's pear season - and two quarts of pears cost a mere $2 at the farmer's market - it's finally time for this pear butter that i bookmarked back in august. it's a play on one of my all time favorite combinations: caramel and fresh fruit. and if you love that combination even half as much as i do, this pear butter is to die for.

caramel pear butter
adapted from bon apetit
makes three full pints

3 tablespoons apple juice or water
4 1/2 tablespoons fresh lemon juice, divided
5 pounds ripe pears
2 1/4 cups light brown sugar
3/4 teaspoon fresh ground nutmeg
1/2 teaspoon kosher salt

1. combine apple juice or water and three tablespoons lemon juice in a heavy, large pot. peel, core, and cut the pears into evenly sized chunks and add to the pan. toss with the lemon juice to keep the pears from turning brown.
2. cook over medium heat until pears start to boil, about fifteen minutes. reduce heat to low, cover, and cook about twenty minutes, until pears are tender, stirring every five minutes to make sure the pears don't scorch.
3. using an immersion blender, puree the pears until smooth. 
4. add the remaining one and a half tablespoons of lemon juice, brown sugar, nutmeg, and salt and stir to combine. bring to a boil and stir to ensure the sugar is dissolved. once boiling, turn the heat down so the mixture is at a low simmer. simmer uncovered for about an hour, until thickened. be sure to stir the mixture about every five minutes to ensure it doesn't burn.
5. while the pear butter is cooking down, prepare your jars, lids, rings, and water bath canner.
6. when the butter is finished cooking, ladle into hot jars, leaving about a half inch headspace. screw on the lid and process in a boiling water canner for ten minutes. 
7. store in a cool, dry place.