* 1 cup unsalted butter, cold
* 8 oz. bittersweet chocolate, chopped fine
* 4 eggs
* 3 cups sugar
* 2 tsp real vanilla extract
* 1 1/2 cups all-purpose flour
* 1/4 tsp salt
* 8 big peanut butter cups, chopped up
1. Preheat oven to 400 degrees and coat a 9x13 baking pan with a little butter.
2. Put 1 cup butter and bittersweet chocolate in heavy saucepan over low heat and melt, stirring and watching closely; set aside.
3. Put eggs and sugar into a bowl and mix with a beater on medium high speed until light yellow and fluffy. Lower the beater speed and slowly add the chocolate mixture, then add the vanilla, keeping the beater running.
4. Continue with the beater on low speed and slowly add flour, incorporating flour before adding more, then sprinkle in salt, mixing well. Stop beater, and with large spatula, fold in the chopped up peanut butter cups.
5. Transfer the mixture into your buttered baking pan. Bake in preheated oven about 30 to 35 minutes, or until knife inserted in center comes out clean and the edges pull away from the pan.
6. Remove from oven and let cool in pan, then cut into squares.