recipe slightly adapted from Gimme Some Oven
2 1/2 Cup cake flour
1 1/4 tsp. baking powder
1/4 tsp. baking soda
1 tsp. kosher salt
1 3/4 Cups sugar, divided (use 1/4Cup for egg whites)
3 egg whites, room temp
pinch of cream of tartar
6 egg yolks, room temp
10 Tbsp. unsalted butter, melted and cooled to sl. warm
1 Tbsp. vanilla
3 Tbsp. vegetable oil
1/2 Cup golden rum
Spray a Bundt pan liberally with nonstick baking spray or butter. Add in a few tablespoons of sugar and coat the pan until the entire pan is coated; ensuring that you also get the middle core.
In a bowl combine the dry ingredients; including 1 1/2 cups sugar and whisk; set aside.
In a stand mixer bowl with the whisk attachment (make sure it is super clean) place the 3 egg whites and a pinch of cream of tartar and whisk until starts to get foamy. Gradually start adding the remaining1/4 cup of sugar about a tablespoon at a time until they reach stiff peaks. Scrape out the whipped egg whites into a medium bowl.
In the same mixer bowl (no need to clean) place the dry ingredients. In a separate bowl whisk together the egg yolks, buttermilk, oil, vanilla, rum, and melted butter. Pour in the egg mixture on medium low speed and mix for about 15 seconds. Stop the mixer and scrape the bottom and sides of the bowl and mix again for 15 seconds until combined. Stop the mixer and fold in 1/3 of the egg whipped egg whites to lighten the batter. Add in the rest of the whipped egg whites and gently fold through to combine. Pour the batter into the prepared Bundt pan and spread even on top. Bake in the center of the oven for about 40 minutes or until when a wooden skewer returns with moist crumbs.
While the cake is baking, make the butter rum syrup.
Remove the cake from the oven and let cool over a wire rack for a few minutes. Poke the cake all over with a long wooden skewer and then pour over 1/2 of the rum syrup. Let the cake rest for 30 minutes, then invert the cake a slowly pour over the remaining syrup and allow to soak in before serving. Cover any unfinished cake and leave at room temp so the cake does not dry out.
Butter Rum Syrup:
1/4 Cup water
1 Cup sugar
1/2 (1 stick unsalted butter)
6 Tbsp. rum (I used 3 Tbsp. Golden Rum and 3 Tbsp. Meyers dark rum)
In a small saucepan place the water and sugar and heat until sugar starts to dissolve; a few minutes. Add in the butter and heat until boiling; and continue to boil for 5 minutes. Remove from the heat and add in the rum and stir.