Place as many slices of bread as possible on a large cookie sheet. Toast about 6 minutes on each side or until golden. Remove from heat, place toast on a paper towel to cool. Repeat until all bread is toasted.
In a food processor, tear 4 pieces of toast into small pieces, add about 1/2 teaspoon of the oregano, and pulse until a crumb consistency. After all the toast is crumbed, return crumbs to the cookie sheet and toast about 6 additional minutes. Remove the cookie sheet from the oven and place crumbs in a large bowl. Add any remaining oregano to crumbs, toss to combine.
Allow crumbs to cool completely, place in an airtight container and store in the refrigerator up to 2 months.
It's necessary to toast the bread crumbs in two stages in order to remove moisture. Making your own bread crumbs is easy and perfect for coatings and in stuffing.