Set the oven to 350F. Coat a standard 10 cup bundt pan very thoroughly, pushing grease into every groove and corner so the cake releases cleanly. A baking spray made with flour or a homemade butter and flour paste works best.

Whisk the flour, cinnamon, nutmeg, cardamom, allspice, salt, baking powder and baking soda together in a medium bowl until evenly blended, then leave it aside.

Stir the apple cider and applesauce together in a large measuring cup. Leave it at full strength, since the applesauce supplies all the moisture the cake needs.

In a large bowl, beat the oil with the dark brown sugar and granulated sugar until the mixture turns glossy and loose instead of looking like wet sand.

Beat in the eggs one at a time, mixing well after each addition, then add the vanilla and beat until the batter looks smooth and has lightened a shade.

Add the dry mixture and the cider mixture to the sugar mixture in alternating batches, starting and finishing with the flour. Mix only until the last dry streaks vanish, and no longer.

Scrape the batter into the prepared pan and level the top. Bake for 40 to 50 minutes, until a wooden skewer pushed into the deepest part comes out clean.

Let the cake rest in the pan for 10 minutes, then turn it out onto a cooling rack placed over a baking sheet. While the cake is still warm but not too hot to touch, brush it all over with melted butter and press on a generous layer of cinnamon sugar. Give the crust a few minutes to set before cutting.