Pre-heat oven to 350°F.
Spread cake cubes in a 9 x 13-inch baking pan or similar sized oval baking pan.
In a large bowl, whisk eggs until well beaten.
Whisk in the milk, sugar and vanilla.
Pour milk mixture over the banana bread cubes.
Bake for 30 - 40 minutes or until custard is set.
May be served warm or chilled; with ice cream or Cool Whip.