Place your oven rack in the middle position and preheat the oven to 350°F.
Grease a bundt pan or tube pan with solid vegetable shortening and sugar (of flour whichever one you prefer.) Set the pan on a large cookie sheet to catch any overflows.
In a medium-size bowl, combine the dry ingredients: Sifted then measured flour, baking powder, salt, and cinnamon. Stir to combine.
In the bowl of your electric mixer fitted with the paddle attachment, add room temperature butter and brown sugar. Mix on medium-low until fluffy about 3 minutes. Stop the mixer and scrape the sides and bottom of the bowl with a spatula.
Add the eggs one at a time to the butter mixture waiting until you don't see any yellow before adding the next egg. Continue with remaining eggs. Stop the mixer and scrape the sides and bottom with a spatula.
Combine the buttermilk, vanilla, rum, and bananas in a small bowl and stir.
Return the mixer to low. Add the flour mixture alternately with the buttermilk mixer beginning and ending with flour. Stop the mixer and scrape the sides and bottom. Mix to combine.
Stop the mixer and fold in the pecans by hand.
Pour the batter into your prepared pan.
Bake at 350°F for 50 minutes. (As always, the time it takes to bake depends on the oven and the pan you use. Watch the cake closely the first time you make a recipe and make note of the time and pan for later.)
Cool 20 minutes in the pan before inverting on a serving tray.
FOR THE PRALINE FROSTING
Bring the sugar, butter, milk, and salt to a boil. Boil 3 minutes stirring often.
Remove from the heat. Add baking powder and vanilla and whisk.
Whisk by hand or beat at med speed with an electric mixer for 5 to 7 minutes or until it begins to thicken.
Stir in tablespoon heavy cream and pecans. Drizzle over pound cake.
Store cake in an airtight container in the refrigerator.