In a bowl, whisk together the flour, baking powder, baking soda, salt and lemon zest.
In a liquid measuring cup, pour the required amount of rum and limoncello. You can measure the rum and limoncello separately; I saw no reason to do so since they would be added to the batter at the same time anyway.
To the softened butter, add the sugar. Cream the butter and sugar until light in texture. Use a wire whisk or an electric mixer.
To the creamed mixture, add the eggs, one at a time, beating after each addition.
Add the flour mixture and cream alternately, mixing after each addition, starting and ending with the flour.
Pour in the vanilla essence and stir to incorporate.
Finally, add the combined rum and limoncello. Mix until smooth.
Pour the batter into the cake pan, scraping the bowl with a rubber spatula to get all the batter into the pan.
Run the spatula on top of the batter to level it as much as possible.
Bake at 350F for an hour.
Cool the cake in the pan for about 20 minutes. While still warm, using a skewer, liberally pierce the cake in several places all the way to the bottom.
Mix the syrup ingredients together.
Pour the syrup over the cake little by little, making sure that each hole catches some of it.
Allow the cake to cool some more then chill in the fridge overnight.
Invert the rum cake with limoncello on a plate, dust with powdered sugar, slice and serve.
Rum cake with limoncello printed from https://casaveneracion.com/rum-cake-with-limoncello/ for personal use only. Not for republication nor distribution.