You should preheat oven to 350F. Whip the egg whites with a mixer until they are thick.
Beat egg whites and sugar until soft peaks. Shortening, chocolate syrup, water, fudge, and vanilla.
Separately, mix flour, cocoa, salt, and baking soda. Slowly add dry ingredients while beating wet.
Shorten an 8-inch cake pan. Spread brownie batter with the chopped walnuts. Bake for about 35 minutes, or can check toothpick comes out clean.
Cut the chilled brownie cake into 9 pie halves. Serve brownies and frozen yogurt with warmed chocolate sauce.