Preheat oven to 300 degrees. Cut bread slices into 1/2" cubes and place in two 13x9" baking pans. Toast bread cubes at 300 degrees for 45 minutes, or until toasted, stirring occasionally. Remove from oven and cool slightly. In large bowl, mix together onion, garlic salt, seasoned pepper, oil, parsley flakes, and sage. Lightly toss bread cubes with seasonings to coat cubes. Place in a large airtight container and label "Herbed Stuffing Mix". Store in a cool, dry place and use within 3 to 4 months. Use in any recipe calling for stuffing mix. Makes about 12 cups
