- 9 ounces unsulfured dried apples (4 cups)
- 4 cups unfiltered apple cider
- 3 cups water
- 1/2 teaspoon ground mace
- 6 tablespoons packed light brown sugar
- 1/2 cup whole milk
- 1/2 tablespoon cider vinegar
- 2 cups all-purpose flour
- 1/2 teaspoon baking soda
- 1/2 teaspoon salt
- 1/2 teaspoon ground ginger
- Pinch of ground cloves
- 6 tablespoons unsalted butter, softened
- 6 tablespoons packed light brown sugar
- 1/2 cup molasses (not robust or blackstrap)
- 1 large egg
- Equipment: 2 muffin pans with 12 (1/3- to 1/2-cup) muffin cups each
- Accompaniment: lightly sweetened whipped cream
- Simmer all filling ingredients and a pinch of salt in a 4- to 5-quart heavy pot, uncovered, stirring occasionally and mashing apples with a potato masher as they soften, until a thick purée forms, about 1 1/2 hours. Cool completely.
- Preheat oven to 350°F with rack in middle. Butter muffin cups.
- Stir together milk and vinegar and let stand 10 minutes to curdle.
- Sift together flour, baking soda, salt, ginger, and cloves.
- Beat butter and brown sugar with an electric mixer at medium speed until pale and fluffy, about 3 minutes. Beat in molasses and egg. At low speed, add flour mixture in 3 batches alternately with curdled milk, beginning and ending with flour mixture and mixing until each addition is just incorporated. Spread 1 heaping tablespoon batter in each muffin cup and bake just until a wooden pick inserted in center of a cake comes out clean with some crumbs adhering, 11 to 13 minutes. Cool 5 minutes in pans on racks, then invert onto racks to cool completely.
- Spread about 2 tablespoons filling on top of 1 cake and invert another cake over filling, then spread a heaping tablespoon filling on top. Make 11 more stacks (you will have about 2 cups filling left over). Transfer to an airtight container and chill at least 2 days for flavors to develop. Bring to room temperature before serving.