Save leftover bread and dry it (either out on your counter or in the oven at 120ºC for about 15 minutes) until completely dry and crisp.
Using your food processor, blender, or by rolling with a rolling pin between sheets of waxed paper, make fine bread crumbs. Save these crumbs. They are useful in a wide variety of ways.
When you have an ample supply, take out 2 cups and mix with the remaining ingredients noted above.
Store in an airtight container in your refrigerator and use within 2 months.