Cake: Position a rack in the center of the oven. Preheat the oven to 350 degrees F. Liberally butter and flour a 10-inch tube or Bundt pan.
Sift the flour, baking powder and salt into a large bowl. In another large bowl, using an electric mixer beat the 1 /12 cups of butter and sugar until light and fluffy. Add the eggs, beating well after each addition. In batches, add the flour mixture, alternating with the buttermilk and ending with the flour mixture.
Pour the batter into the prepared cake pan. Bake until the cake is golden and a cake tester inserted into the center comes out clean, about 45 to 50 minutes. Transfer the cake to a wire rack and cool completely in the pan. Invert the cake onto the wire rack, then put it on a cake plate or platter. (Cooks Note: The cake can be prepared 1 day ahead. Cover tightly with plastic wrap and store at room temperature.)
Topping: Combine the mango, water, sugar cream cheese and tequila, if using, in a blender or food processor. Blend until smooth and thick, adding extra water, if needed. Taste and adjust the sweetness with extra sugar, if needed.
Spoon the mango topping evenly over the top of the cake and decorate with edible flowers, if desired