If you love the apple-cider doughnuts often sold at farmers' markets, you'll love this cake! Baked in a Bundt pan, it's essentially a giant cakey doughnut, made a little more wholesome with whole-wheat flour. A blend of olive oil and applesauce helps keep it moist. This classic fall dessert recipe appears in our cookbook, "A New Way to Bake" (Clarkson Potter). Martha also made this recipe on "Martha Bakes" episode 802.
Preheat oven to 350 degrees. Butter and flour a 12-cup Bundt pan. In a large bowl, whisk together both flours, baking powder, 1 teaspoon cinnamon, baking soda, and salt. In another bowl, whisk together 1 1/2 cups sugar, cider, oil, applesauce, vanilla, and eggs. Add egg mixture to flour mixture; whisk until combined. Transfer batter to prepared pan.
Bake, rotating pan halfway through, until a tester inserted in center comes out clean, 45 to 50 minutes. Transfer pan to a wire rack set over a rimmed baking sheet; let cool 15 minutes. Meanwhile, mix together remaining 1/4 cup sugar and 1/2 teaspoon cinnamon.
Invert warm cake onto rack. Brush with melted butter, then sprinkle liberally with cinnamon sugar. Let cool completely before serving. Cake can be stored, covered, at room temperature up to 2 days.
Bundt pans need to be generously buttered and floured so cakes don't stick; use a pastry brush to be sure to get into all the crevices.