Preheat oven to 375°.
To prepare chips, cut each tortilla into 8 wedges; arrange tortilla wedges in a single layer on 2 baking sheets coated with cooking spray. Sprinkle wedges with 1/2 teaspoon salt and chile powder; lightly coat wedges with cooking spray. Bake at 375° for 12 minutes or until wedges are crisp and lightly browned. Cool 10 minutes.
To prepare guacamole, peel papery husk from tomatillos; wash, core, and finely chop. Combine tomatillos, onion, and remaining ingredients; stir well. Serve guacamole with chips.