Storage: Store the cake covered at room temperature for up to 2 days, or refrigerate for up to 5 days. Bring to room temperature before serving for best texture.
Substitutions: If you cannot find banana-flavored yogurt, you can use plain Greek yogurt and add an extra teaspoon of vanilla or a splash of banana extract. For a non-alcoholic version, omit the creme de banana and use additional banana puree or extract in the syrup.
Tips: Ensure bananas are very ripe (spotted) for the best flavor and sweetness. Do not overmix the batter after adding the flour to keep the cake tender.