If you want to make larger peanut butter granola clusters, ensure the mixture is wet, not crumbly, before transferring it to the pan. Using a liquid sweetener (and increasing the amount) can also help. Also, press the mixture into the baking pan before baking and ‘flip’ it with a spatula rather than stirring it while it bakes. Then leave it to cool COMPLETELY before breaking it into pieces (it hardens as it cools).