Combine the first twelve ingredients in a food processor. Whirl together until crumbs are very small. Store in airtight container. This will make approximately 3 cups and will keep for up to a year in a cool, dry place.
To Make into a Dressing:
Using a food processor or blender, mix together mayonnaise, buttermilk, and dressing mix. May add more dressing mix, to suite your taste preference.
Pour into a pint jar or serving vessel. Cover and allow to chill for 4 hours. Pour over your favorite lettuce salad. This will make approximately 2 cups of dressing.