Cut the bread into the thinnest possible slices; remove the crusts and cut each slice in half.
Place in a layer directly on the oven racks in a preheated oven.
Bake at 250°F (120°C) for 10 minutes.
Turn off the heat and allow the toasted slices to cool in the oven.
Then store in a tightly sealed container in refrigerator or freezer.