Preheat the oven to 325 degrees F. Beat the egg whites until thick. Blend the egg whites with the cake mix and water. Pour the batter into a greased 9x12-inch baking pan. Bake for 30 minutes, or until the top is golden brown and a toothpick inserted in the center comes out clean. Cool. For the frosting, melt the butterscotch morsels in a microwave oven on high for 45 seconds. If you don't have a microwave oven, use a double boiler over hot, not boiling, water. Mix the butter with the melted butterscotch. Add the powdered sugar. Blend with a mixer until the frosting has a smooth consistency. Spread the frosting on top of the cooled pound cake. Cut the cake into nine rows. Then make two cuts lengthwise. This should divide cake into twenty-seven equal pieces.