Spray a 18cm x 25cm x 2cm nonstick baking pan with vegetable cooking spray. Lay a 15sm by 45cm piece of parchment paper in the pan, allowing the excess paper to hang over the sides. Spray the parchment paper lightly with cooking spray.
In a medium bowl, using a hand beater, beat the egg white until frothy. Stir in the peanut butter, brown sugar, and honey. Add the melted butter, oats and almonds. Stir to combine, then add the chocolate chips.
Using a rubber spatula, spread mixture into the prepared baking pan, pressing lightly to form an even layer. Bake until the edge of the mixture begins to brown, about 15 minutes. Remove from the oven and let cool for at least 1 hour. Cut into 4cm squares and serve.
*Cook's Note: To toast almonds, arrange in a single layer on a baking sheet. Bake in a preheated 175°C oven until lightly browned, about 8 to 10 minutes.