Step 1

Thoroughly grease and flour a Bundt pan. Sprinkle the pecans into the bottom of the pan.

Step 2

To make the cake, combine the sugar and butter in the bowl of a stand mixer fitted with the paddle attachment. Beat on medium-high speed, scraping down the sides as needed, until light and fluffy, about 8 minutes.

Step 3

Reduce the mixer speed to low. Beat in the whole eggs, one at a time, followed by the egg yolk and the vanilla. Continue to beat until smooth. Turn off the mixer.

Step 4

In a large bowl, whisk together the flour, baking powder, and salt.

Step 5

In a large measuring cup or small mixing bowl, whisk together the buttermilk and rum.

Step 6

Add about a quarter of the dry ingredients to the stand mixer and, on low speed, gently mix to incorporate. Mix in a quarter of the wet ingredients. Repeat until the all of the dry and wet ingredients are fully incorporated.

Step 7

Spoon the batter into the prepared pan. Place in the oven and bake until a toothpick inserted into the center of the cake comes out clean, about 45 minutes. Place on a wire rack but don’t remove the cake from the pan.

Step 8

Meanwhile, make the citrus-rum syrup. Melt the butter in a medium saucepan over medium heat, then, when the butter is foamy, stir in the sugar and orange juice. Bring to a boil. Continue to boil, stirring constantly, for 5 minutes. Remove the pan from the heat and add the rum. Return the pan to medium heat and cook, stirring, for 30 more seconds, then remove from the heat and set aside.

Step 9

While it’s still in the Bundt pan, poke the cake about 100 times with a skewer or the food probe. Pour about one third of the rum syrup over the cake. Let rest for about 5 minutes.

Step 10

Carefully turn the cake out onto a cake stand. Poke another 100 holes in the top of the cake and drizzle another third of the rum syrup all over the top of the cake. Let rest for 30 minutes.

Step 11

Use the remaining syrup to glaze the cake before serving.