Sweet Potato Layer Cake

My sister just turned 21 last weekend, hooray. So a few weekends ago, while she was home for her Fall break, I made a cake. I wanted something autumn-y but still birthday-ish and not too cliche. I ended up making a sweet potato cake. This recipe is great because it's moist, it's low-fat, and it's awesome for this cool, crisp season.

Ingredients:
1 cup mashed sweet potato (1 large sweet potato, about 1 lb)
1-1/2 cups cake flour (or all purpose - cake flour will yield a more tender cake)
1/2 teaspoon salt
1 teaspoon baking soda
1 teaspoon baking powder
1 teaspoon cinnamon
1/2 teaspoon ground ginger (or 1 teaspoon freshly grated ginger) - not pictured
pinch of ground cloves
1/4 teaspoon nutmeg - not pictured
1/4 cup vegetable oil
1 cup packed brown sugar
1 cup unsweetened applesauce
2 large eggs
1 teaspoon vanilla extract
1 cup heavy cream
1/2 cup mascarpone
2 tablespoons powdered sugar
+ butter & flour for greasing the baking pan

*So, I have walnuts in this photo here but I totally forgot to use them in the recipe.

Start by roasting the sweet potatoes. I lined a baking sheet with foil (EASY CLEAN UP), poked the tubers with a fork (this is to help the steam escape so they don't explode in the oven), and baked them in a 400 degree oven for about 1 hour until they were soft and cooked through. You'll see that some of the juices will escape and then caramelize because sweet potatoes are full of sugar.

Let the sweet potatoes cool until they are handle-able without burning your fingers. You can even roast them the night before, wrap them up in some foil (reuse the foil you used to line the baking pan) and then deal with them the next day when they're 100% completely cooled. Peel the skin, which should be easy if you let them cool sufficiently, and then mash them until they take on the consistency of baby food. Measure out 1 overflowing cup and set aside. I'll post about what to do with the leftovers tomorrow.

Grease a baking pan - I used a round springform pan - and then flour it. We don't want the cake to stick.

Sift together the dry ingredients (flour, baking soda, baking powder, cinnamon, ginger, nutmeg, salt, and cloves). I like to sift them a few times just to get it aerated and fluffy.

In another bowl, measure out the brown sugar, oil, and applesauce and whisk together. Applesauce is a GREAT ingredient in cakes because it adds a lot of moisture and sweetness so that you don't need to use as much oil and/or sugar. [[Here's an awesome tip: the next time you are making a boxed cake mix, substitute the oil with applesauce. The cake will be "fat free" and moist and amazing but still taste like it's "fat full." Also, another amazing thing about applesauce batter is that when you're doing the dishes, everything rinses off so easily because there's no oil to adhere the batter to the bowls!]] Then add in the eggs, one at a time, and whisk until combined. Dump in the sweet potatoes and mix and then finally, add in the vanilla extract. Once the wet ingredients are combined, add in the dry ingredients, in about 3 installments, and slowly whisk just until combined.

Do NOT overmix the batter, especially if you're using all purpose flour instead of cake flour. It will get chewy like a sweet potato bread instead of being tender like a cake.

Pour the batter into the greased and floured pan and bake in a 350 degree oven for 25 to 30 minutes until a toothpick inserted in the center comes out clean.

See how pretty it looks when it's baked? Leave alone to cool for 1 hour.

Meanwhile, assemble the topping. Whisk heavy cream and powdered sugar on high speed until a fluffy, spreadable whipped cream forms. Then add in mascarpone, which should be at room temperature to make this step easier, and fold into the whipped cream.

To assemble the cake, I cut mine into two layers (which isn't necessary) and spread a bit of whipped cream in the center. Then I put the two layers together and spread on a thin layer of topping around the entire cake. And because I was feeling fancy (also because this was meant to be a birthday cake), I filled a piping bag with a star tip and piped little rosettes around the outside of the cake. The texture of the topping wasn't really conducive to piping this way (it was just too airy and the bag kept "farting") but it still came out pretty. Once the cake is piped, refrigerate until you're ready to serve.

Looks kind of like a wedding cake almost, doesn't it?

Seriously, SO yummy. You can see how the cake looks a bit more airy in the top layer and denser on the bottom. I'm speculating, but I think that the heavy ingredients (like sweet potato and applesauce) helped to compress the cake.

Grab a bite and enjoy! This cake is moist, flavorful, and the sweet potato, cinnamon, cloves, nutmeg, and ginger really make it taste like autumn.

Here's the recipe page: