1. Preheat oven to 400°.
2. Split each pita in half horizontally; cut each half into 6 wedges. Arrange pita wedges, rough sides up, in a single layer on a large baking sheet. Lightly coat wedges with cooking spray; sprinkle with garlic salt. Bake at 400° for 9 minutes or until golden brown and crisp. Cool completely.
3. Place yogurt and next 8 ingredients in a food processor; process until smooth. Pour into a serving bowl; cover and chill at least 30 minutes. Serve with pita chips.