In a saucepan over medium heat, bring sugar, butter and water to a boil; remove from the heat. Stir in 1 cup of chocolate chips and vanilla; stir until smooth. Cool for 5 minutes. Beat in eggs, one at a time, until well mixed. Combine flour, salt and baking soda; stir into chocolate mixture. Stir in another cup of chips. Pour into a greased 9-inch square baking pan. Preheat oven to 325 °F. Bake for 35 minutes. Cool completely. Place in the freezer for 30-40 minutes (do not freeze completely). Cut into bars.

In a microwave or double boiler, melt remaining chips with shortening; stir until smooth. Using a small fork, dip brownies to completely coat; shake off excess. Place on waxed paper-lined baking sheets; immediately sprinkle with nuts. Allow to harden. Store in an airtight container in a cool place.