Caribbean Buttered Rum Cake

In a large bowl, combine first 6 ingredients.
On low speed, combine ingredients until the mixture is the consistency of sand, and all particles are generally the same size.
Preheat oven to 325F.
Grease a large Bundt pan (12-cup capacity).
Sprinkle chopped nuts onto bottom of the pan.
Place mix from step 2, pudding mix, milk, eggs, rum, vegetable oil, and vanilla in a large bowl. Combine on slow speed until just mixed, about 30 seconds.
Increase the mixing speed to medium and beat for 2-3 minutes, until the batter is smooth and cream-coloured. Scrape down the bowl halfway to make sure everything is well incorporated.
Scrape the cake batter into the prepared Bundt pan. Bake for about 55 minutes or until a wooden skewer inserted into the cake comes out clean.
Remove the cake from the oven and place on cooling rack while you make the Buttered Rum Glaze.
Combine butter, water, and sugars in a small saucepan. Bring to a boil over high heat.
Turn the heat down and simmer until sugar is dissolved and syrup thickens, about 5 minutes.
Remove the pan from the heat and stir in the rum.
While the cake is cooling in its tin, brush the cake with the syrup until the syrup is all used up.
Let the cake cool completely before turning it out onto a platter, although it's best if you let it sit for a few hours to fully absorb all the syrup.