Wash hands with soap and water for 20 seconds.
Preheat oven to 325°F. Spray a large shallow baking pan with non-stick cooking spray; set aside.
Put egg whites in large bowl; mix until frothy. Stir in honey, cinnamon, vanilla, and salt.
Add oats plus nuts and/or dried fruit, if desired. Stir until oats are coated with egg mixture. Spread oat mixture evenly on prepared baking sheet.
Wash the counter and utensils that touched the raw egg. Washhands with soap and water after handling raw egg.
Bake about 25-30 minutes until golden brown; stir mixture carefully every 5 or 6 minutes to prevent overbrowning.
Remove pan to wire rack and cool completely until crispy and crunchy. Store in airtight container.