Preheat the oven to 350ºF (180°C). Line a baking sheet with a piece of parchment paper cut to fit.
Thoroughly beat the egg white until light, frothy, and white. Just use a whisk for this. Then, using a fork, mash the banana and use that same fork to stir it into the egg whites to make a thick batter with tiny chunks of banana in it.
Add the oats and stir in the nuts.
Using a small ice-cream scoop or two tablespoons, form little dollops of the batter and dot them out on the prepared baking sheet.
Bake the banana dollops for 15 minutes, until light brown.
Eat them immediately or keep them in an airtight (resealable) bag or container. They will keep for about 4 days. Handy as a snack and super-duper healthy to boot.
Home Baked by Yvette van Boven, published by Stewart, Tabori & Chang (£25.00), buy it from Abrams & Chronicle Books.
Images © 2015 Oof Verschuren.