While bread is toasting, combine the remaining ingredients except the onion in a food processor and process until smooth. Transfer to a medium-size bowl and mix in the red onion. Serve the olive tapenade with the toasted pitas alongside.
Preheat the oven to 350°F.
Arrange the pita bread wedges on a cookie sheet in a single layer (use 2 cookie sheets if you run out of room). Transfer to the oven and toast for about 10 minutes or until golden and crispy.