Equipment Needed
- 9×13 inch baking pan
- Parchment paper
- Electric hand mixer or stand mixer
- Large mixing bowls
- Whisk and rubber spatula
- Potato ricer or fork for mashing
- Measuring cups and spoons
- Toothpick or cake tester
Step-by-Step Instructions
I always start by roasting my sweet potato—pierce it a few times, pop it on a baking sheet, and let it bake at 400°F for about 45-60 minutes until it’s completely soft. Once it’s cool enough to handle, I scoop the flesh into a bowl and mash it until absolutely smooth. A few stringy bits are okay, but you want it mostly creamy. This is the secret to that velvety texture in the final cake. While it cools, I prep my pan by lining it with parchment paper and lightly greasing it. Trust me, this makes cleanup a dream and ensures your beautiful cake comes out in one piece.
Now, for the magic. In my mixer bowl, I combine the softened butter and sugar. I beat it on medium-high for a full 3-5 minutes. I’m not kidding when I say to let it go until it’s pale, fluffy, and almost white. This step incorporates air and is the foundation of your cake’s texture. I then add the eggs, one at a time, letting each fully incorporate before adding the next. The mixture might look a bit curdled after the eggs—that’s fine! Then, I beat in the mashed sweet potato and vanilla. The batter will smell incredible already, taking on a beautiful orange hue.
In a separate bowl, I whisk together all my dry ingredients: the flour, baking powder, baking soda, salt, and spices. I give them a good stir to ensure the leavening agents are evenly distributed. Here’s the crucial part for a tender crumb: I add the dry ingredients and the buttermilk to the wet mixture in three alternating additions, starting and ending with the dry. I mix on low speed and stop just as the last streaks of flour disappear. Overmixing is the enemy of a soft cake! I finish by folding everything together with a spatula to make sure nothing is hiding at the bottom.
I pour the thick, fragrant batter into my prepared pan and smooth the top. Then, it goes into a preheated 350°F (175°C) oven. The waiting is the hardest part! I set my timer for 45 minutes but don’t even think about opening the oven door before then. At 45 minutes, I start checking with a toothpick inserted into the center. In my oven, it usually takes 50-55 minutes. You want a few moist crumbs clinging to the toothpick, not wet batter. The top will be a gorgeous golden brown and will spring back lightly when touched.(See the next page below to continue…)