For the cake: Position an oven rack in the middle of the oven and preheat to 325 degrees F.
Spray a 12-cup Bundt pan with cooking spray and sprinkle the bottom with the chopped pecans. Set aside.
Combine the flour, dry milk, cornstarch, baking powder and salt in a large bowl. Set aside.
Cream the butter and sugar together in a stand mixer fitted with the paddle attachment on medium speed until light and fluffy.
Add the dry ingredients and mix until combined. (It will look like crumb topping.)
Whisk together the milk, rum, oil, vanilla and eggs in another bowl.
Slowly add the liquid mixture to the crumb mixture and mix until combined. (Pouring the liquid in slowly is important. The batter has a high ratio of liquid and will be thin almost like a thick crepe batter, but if you add the liquid too quickly you will get lumps that never go away no matter the amount of mixing!)
Pour the batter into the pan and bake until the top is golden, center is set and a toothpick comes out clean when inserted, 50 to 60 minutes.
Let the cake cool in the pan for 10 minutes, then invert onto a cooling rack. Poke holes all over the cake using a wooden skewer.
For the buttered rum sauce: Meanwhile, add the butter, honey, cinnamon, cardamom, allspice, nutmeg, salt and 1/3 cup water to a medium saucepan over medium heat. Cook, stirring, until the honey has dissolved, 1 to 2 minutes. Remove from the heat and stir in the rum. (It is going to bubble and splatter a little, so be careful.)
Clean and dry the Bundt pan, then place the cooled cake back inside the pan. Poke a few holes in the top. Evenly pour the rum sauce over the cake. Let the cake sit to absorb the sauce, 30 minutes or up to overnight.
Invert the cake back onto a cake plate and serve at room temperature. (See Cook's Note.)
You can also serve this cake cold? I know it's called hot buttered rum cake but I LOVE this cake when it's cold.
This recipe has been updated and may differ from what was originally published or broadcast.