Preheat the oven to 350°. Wrap the allspice, cloves, fennel seed, black peppercorns, cinnamon stick and star anise in a small piece of cheesecloth. Using twine, tie the cheesecloth into a bundle.

In a large bowl, toss the apples with 6 tablespoons of the lemon juice and the brown sugar. In a large Dutch oven, melt the butter. Add the apples and cook over moderately high heat, stirring occasionally, until they begin to let off moisture, about 5 minutes. Put the spice bundle in the pot, cover and transfer to the oven. Bake for about 1 hour and 30 minutes, until the apples have softened.

Discard the spice bundle. Add the remaining 1 tablespoon of lemon juice to the apples, season with sea salt and stir until a chunky sauce forms. Scrape the applesauce into a bowl and serve warm or cover and refrigerate until chilled. The applesauce can be refrigerated in an airtight container for up to 5 days.