Sooner or later, every home baker forgets to add an ingredient to a batter or dough. Leaving the eggs out of the banana bread isn't the worst mistake you can make. Fix it if you can, but don't agonize if the bread has already been baked. Toast it to improve its flavor, or cut it into cubes and make it into a bread pudding.
Eggs' Role in Baking
Eggs play several vital roles in baked goods such as banana bread. The whites contain protein, which helps provide structure so you don't end up with a crumbly or gooey mess. The yolks contain fat, which adds flavor and tenderness. Egg yolks also help give banana bread a golden brown color and can improve leavening. Without eggs, banana bread may be dense, tough or crumbly.
To remedy an unbaked dough, simply crack the eggs in a small bowl and beat them well. Pour the beaten eggs into the batter and stir to combine. The trick is to make sure the eggs are completely incorporated into the dough without overworking it. Like all quick breads, banana bread becomes tough if you stir it too much. Use a rubber spatula or wooden spoon to gently fold or stir the batter, just until the eggs are mixed. Pour the dough into a prepared pan and bake as you normally would.
There's not much you can do about a banana bread that's already in the oven, but take heart. Banana puree is often used as an egg substitute in baked goods, and your banana bread may turn out better than expected. The bread may be slightly denser or tougher, but the moisture in the bananas will compensate somewhat. Quick breads also tend to have more fat than other baked goods, which can help save your banana bread. Forgetting the eggs in cookies or cakes is a much riskier proposition.
Solutions for Next Time
It's easy to become distracted when you're baking and forget to include an ingredient. To solve this problem in the future, set all the ingredients on the countertop before you start mixing. If you forget something, you'll notice it immediately and can remedy the error before disaster strikes.