In a pot on the stove, over very low heat, melt chocolate and shortening, stirring constantly until smooth. Cool completely.
Preheat oven to 350 degrees.
Add sugar and vanilla and stir until well combined.
In a separate small dish mix powdered eggs and 4 Tbsp water.
Add egg mix to pot and continue to stir.
Add flour and nuts to pot and stir until just combined.
Pour batter into a greased 8x8 inch pan.
Bake for 25 minutes, or until a toothpick comes out clean.
Cool completely then cut into squares.