Coat an 8 inch square pan with cooking spray, dust with 2 teaspoons flour.
Place butter in large microwavable safe bowl. Cover and microwave 1 minute, or til butter melts. Add sugar, stir with a whisk. Add vanilla and egg whites, stir well. Stir in buttermilk, salt, baking soda.
Lightly spoon 1 1/2 C flour into dry measuring cups, level with knife. Add flour, stirring JUST till blended. (DO NOT OVERSTIR) Spread half of batter into prepared pan. Add cocoa and almond extract to remaining batter, stir well with a whisk. Slowly pour chocolate batter over batter in pan.
Bake 350 degrees for 30 min or till wooden pick comes out clean. Cool 10 minutes in pan on wire rack. Cut into squares.