Eight bananas mashed into creamed butter and sugar with flour, eggs and vanilla, and baked for an hour. It is a wet batter and a dense cake, and it is what to do with bananas nobody wants to eat.
Eight bananas is a great deal of fruit against two cups of flour, and the batter comes out wetter and looser than most cake batters. That is what this cake is: dense, moist and heavy rather than light. It also means the hour in the oven is genuinely needed and the middle is the last part to set. Use bananas that are properly ripe, skins spotted or black. Underripe banana does not mash to a purée, stays starchy and gives the cake a chalky taste. This recipe exists to use up the ones nobody wants to eat. Grease the tin and then flour it. Flour alone, which is what the instruction said, has nothing to stick to, and a cake this wet will weld itself to the metal. Let it cool in the tin before turning it out for the same reason: hot, it has not set enough to hold together.