The recipe is from "Beat This Cookbook" by Ann Hodgman I'm posting it with the changes I made

Butter an 8" square pan. Pre heat oven to 375

1. In a large bowl beat sugars , eggs and salt for 15 minutes, until very pale. It has got to be 15 minutes( i did it in my stand up mixer)

2. Melt 8 oz chocolate with butter in a double boiler, remove just before totally melted, finish off the heatstirring until chocolate is completely melted.

3. Stir in vanilla and let cool to lukewarm

4.Fold gently into eggs and add the rest of the chocolat.

5. Fold in the flour and the walnuts and pour into prepared pan set in the middle of the oven.

6. Bake 20 minutes.

7. Remove to a rack let cool 6 hours

Original recipe: uses 1 cup white sugar, no brown sugar, no walnuts. 1 c miniaturee chocolate chips are added in place of the walnuts and the grated chocolate that I added at the end. Calls for 5 oz best quality semi sweet chocolate plus 3 oz undweetened chocolate. You may bake 30 minutes if you like them dryer.