Breadcrumbs was my first thought. Spread them out on cookies sheets and allowed to dry further.
I save the last few slices of bread in a loaf, leftover hot dog and hamburger buns. Tear the bread and buns into pieces and spread out on several cookie sheets. Then I place them in the oven to dry out for 24 hours to get good and dry. Process in a food processor or my favorite....my Ninja blender!