When we eat things that are made with what was originally matzah do we make the bracha of hamotzei or mezonot. For example - stuffing made from matzah farfel or cakes made from mazah meal.
If that is the case would we also make a mezonot on crutons that were made by cutting up bread? What about pita chips and bagel chips that were originally made from pita and bagels?
A reasonable sized piece of bagel or challah would be hamotzie.
A reasonable size piece of matzah would be the same.
Croutons made of actual bread would be hamotzie.
Many recipes call for breadcrumbs all year and many call for matzah meal on pesach. These would be mezonot.