This is one scrumptious cake. The All Things Considered staff scarfed the whole thing up, licked the crumbs off their plates, rubbed their bellies, and insisted this was my "best cake ever," "definitely in your Top 10 of cakes," and they begged, "Can I have the recipe?" Sure. Here it is. It should serve 20 to 32.
A shallow baking pan
A potato masher
A 10-inch tube pan
For The Cake
About 4 medium sweet potatoes
2 sticks (1 cup) unsalted butter
1 cup sugar
1 cup dark brown sugar
4 large eggs
3 1/2 cups all-purpose flour
2 teaspoons baking powder
1/2 teaspoon baking soda
1/2 teaspoon ground nutmeg
1/2 teaspoon ground cinnamon
1/2 teaspoon salt
1/2 cup milk
1 teaspoon vanilla extract
1 teaspoon maple flavoring
1/2 cup peeled and diced Granny Smith apples
For The Topping
2 tablespoons cold unsalted butter, cut into pats
2 tablespoons dark brown sugar
3/4 cups chopped pecans
About 2 Hours Before Mixing The Cake
1. Preheat the oven to 325 degrees F. Bake your sweet potatoes for at least 45 minutes. Use a knife or a fork to test for doneness—the potato should be very mushy inside its shriveled skin. Remove from oven and cool for 1 hour. Slit each skin lengthwise and remove, leaving the soft, orange center. Mash with a potato masher and measure out 2 cups for this recipe. Cool to room temperature before mixing the cake. If the mashed sweet potatoes are too warm, they will melt the butterfat and the batter won't get as nice and thick as it should.
To Make The Cake
2. Position a rack so the cake will sit in the middle of the oven, and preheat the oven to 325 degrees F. Line the bottom of your tube pan with parchment paper, and spray the sides and bottom with baking spray.
3. Cream the butter with a mixer on medium speed.
4. Combine the sugars in separate bowl. Gradually add to the creamed butter, 1/4 cup at a time, beating at medium to high speed after each addition.
5. Add the eggs, one at a time, beating at medium to high speed for 1 minute after adding each one.
6. Reduce the mixer to low speed and add the mashed potatoes, 1/2 cup at a time.
7. In a separate bowl, dry whisk together the flour, baking powder, baking soda, nutmeg, cinnamon, and salt.
8. In another separate bowl, combine the milk, vanilla, and maple flavoring.
9. With the mixer still on low speed, alternately add the flour mixture and milk mixture, beating after each addition. Start with a third of the flour mixture, beat, then add half of the milk mixture, beat again, and repeat until the last of the flour mixture has been added and beaten in.
10. Turn off the mixer, scrape down the sides of the bowl with a spatula, and then mix the batter on medium to high speed for 2 minutes.
11. Slow the mixer down to the lowest speed and add the apples, mixing until just incorporated.
12. Pour the batter into the prepared cake pan and use the back of a spoon to even out and smooth the batter.
To Make The Topping
13. In a separate bowl (I know — it's like the bowls have Balkanized here), combine the cold butter, brown sugar, and chopped pecans. Mix with a wooden spoon and do not fret because the mixture is crumbly. That's just the way you want it.
14. Sprinkle the topping all over the surface of the batter.
Bake in the oven for 1 hour and 15 minutes before testing for doneness. Then use a sharp knife to test the cake, and poke it around in a couple of places to determine whether it's finished. This cake can fool ya.
15. Cool in the pan for 20 minutes. Then, using the plate-over-pan method, unmold the cake and flip it onto a cake rack, topping side up.