Preheat oven to 325 F. Butter and flour 2 8x8 square pans.
Cream shortening in mixer for about 3 minutes. Add sugar and eggs, alternating and beat well.
Melt chocolate in a double boiler, or in a glass dish over simmering water. Blend melted chocolate into sugar mixture, stir in salt and vanilla.
Whisk together flour and baking powder then stir into chocolate mixture. Stir in nuts.
Bake for 30-35 minutes. Let cool in pan before cutting into squares or rectangle bars.