1. Drop chocolate into boiling water. Boil briskly for 1 minute.
2. Add sugar and butter. Let cool.
3. Sift together flour, salt and baking soda. Add to cooled chocolate mixture.
4. Stir in eggs and vanilla
5. Pour into buttered spring form pan. Bake at 250 for 1 1/2 hours or until done.
Note: The batter is very thin and yes, the temperature is correct.