If you want, cut the crusts off the bread. If the bread is very, very dry, break it in pieces, place the pieces in a food processor with the sharp mixing blade, and process until the crumbs are the consistency of grainy sand. If the bread is not completely dry, tear it into ½-inch (1.2-cm) pieces and toast these in a 325 degrees Fahrenheit (165 degrees Celsius) oven until a test piece crumbles between your fingers; timing will depend on the freshness of the bread. Turn the heat down if the bread is getting too dark. Process as above. Place in a plastic bag and freeze for up to 6 months. Use as needed.