1. Heat oven to 350°F. Grease bottom only of 8-inch square baking pan.
2. Stir together sugar, flour, cocoa, baking powder and salt in medium bowl. Add oil, eggs, milk and vanilla; beat until smooth. Pour batter into prepared pan.
3. Bake 35 to 40 minutes or until wooden pick inserted in center comes out clean. Cool completely in pan on wire rack.
4. Remove wrappers from caramels. Combine caramels and water in small saucepan. Cook over low heat, stirring occasionally, until smooth and well blended. Stir in pecans; cool until thickened slightly. Cut cake into squares; serve with warm caramel nut sauce and sweetened whipped cream, if desired. 16 servings.