Ingredients
2½cupscake flour
1¼tspbaking powder
1tspsalt
¼tspbaking soda
1¾cupssugar,divided, plus extra for the pan
10tbspunsalted butter,melted
½cupbuttermilk,room temperature
½cuprum
3tbspoil vegetable
1tbspvanilla extract
6largeegg yolks,room temperature
3largeegg whites,room temperature
½cupbutter
¼cupwater
1cupwhite sugar
¼cuprum
Preparation
Adjust oven rack to middle position and heat oven to 350 degrees F.
Grease a bundt pan liberally with cooking spray.
Then add a few tablespoons of granulated sugar to the inside of the pan, and gently tap and turn it around until every square inch of the inside of the pan is coated in sugar. Set aside.
In a large bowl, whisk together cake flour, baking powder, salt, baking soda, and 1½ cups of sugar until combined.
In a different medium bowl or large measuring cup, whisk together melted butter, buttermilk, rum, oil, vanilla, and yolks until combined. Set aside.
In a clean bowl of a stand mixer, beat egg whites at medium-high speed until foamy, about 30 to 45 seconds. With the whisk still running, add in the remaining ¼ cup of sugar.
Continue to beat until stiff peaks just form, about 60 to 90 more seconds. Transfer the whipped egg whites to a separate bowl and set aside.
Add the flour mixture to a now-empty mixing bowl. Using the whisk attachment again, gradually pour in butter mixture and mix on medium-low speed until it is just combined for about 15 seconds.
Stop the mixer and scrape the whisk and sides of the bowl. Return mixer to medium-low speed and beat until the mixture is smooth and fully incorporated about 10 to 15 more seconds.
Fold about ⅓ of the whipped egg whites into the batter until just combined, then add the remaining whites and gently fold in until no streaks remain.
Pour the batter evenly into the sugared bundt pan. Bake for 40 to 50 minutes, or until a toothpick inserted into the middle of the cake comes out clean.
Transfer the cake to a cooling rack and let it cool for at least 15 minutes.
Once the cake is slightly cool, use a toothpick or skewer to poke lots of holes all over the surface of the cake. Pour about half of the butter rum sauce over the surface of the cake.
Let it rest for 5 to 10 minutes until the sauce is absorbed. Carefully invert the cake onto a serving platter or pedestal, and drizzle the remaining sauce evenly on top of the cake.
Serve immediately, or cover until ready to serve.
In a medium saucepan, whisk together sugar, butter, and water until combined.
Bring to a boil over medium-high heat, stirring occasionally, and continue to boil for 5 minutes or until the sugar is completely dissolved.
Remove from heat and gradually stir in rum.
