Preheat the oven to 180°C (th. 6) on the convection setting. Lightly butter a round silicone mold about 20 cm in diameter.
Cream the softened lightly salted butter with the powdered sugar until the mixture is smooth and creamy. Continue beating for several minutes to ensure the sugar is completely dissolved.
Stir in the sifted almond powder, then mix until the mixture is smooth.
Add the eggs one at a time, whisking between each addition to incorporate them thoroughly into the mixture.
Add the sifted flour, then gently fold it in with a rubber spatula to keep the batter smooth and even.
Add the rum to the batter, then mix one last time.
Pour the batter into the pan, smooth the surface, and bake for about 40 minutes. Check to see if it's done by inserting the tip of a knife into the center of the cake.
Remove the cake from the oven, carefully turn it out onto a wire rack, and let it cool completely at room temperature.
To make the glaze, mix the powdered sugar and white rum in a bowl until you have a smooth glaze.
Spread the frosting over the cake and smooth it out with a spatula.
