1. Preheat oven to 350°.
2. Combine first 3 ingredients in a large bowl. Add egg whites and egg, stirring until blended.
3. Lightly spoon flour into dry measuring cups; level with a knife. Combine flour, baking powder, and salt; add to sugar mixture, stirring just until blended. Stir in caramels and pecans. Spread brownie batter into a foil-lined 8-inch square pan coated with cooking spray.
4. Bake at 350° for 23 to 24 minutes (wooden pick will not test clean). Cool completely in pan on a wire rack.