Mix 1/2 cup thick starter, 1 cup water, 1/4 cup non-fat dry milk and 1 1/2 cup flour. Let stand 2 to 3 hours in a warm place until bubbly and has a sour milk odor.
In a separate bowl, cream 1 cup sugar, 1/2 cup shortening, 1 tsp. vanilla, 1 1/2 tsps.
soda, 1 tsp. cinnamon, and 1/2 tsp. salt.
Add 2 eggs, one at a time, beating well after each addition.
Melt 3 sqs. semi-sweet chocolate and add to creamed mixture. Stir 300 strokes or use low speed on electric mixer.
Pour into 2 greased and floured layer pans or 1 9x13 cake pan.
Bake at 350 degrees for 25 to 30 minutes. Cool in pan for 10 minutes. Remove from pans and frost when cool.