Nashville's One-Pan Fudge Cake

8 tablespoons butter
1 1/4 squares bittersweet chocolate
1 cup granulated sugar
2 eggs
1/2 cup all-purpose flour
1/4 teaspoon baking powder
1/8 teaspoon salt
1 teaspoon vanilla extract
1 cup nuts, chopped coarse

Preheat the oven to 325 degrees F. Thoroughly grease an 8-inch square baking pan.

In a medium saucepan over very low heat, melt the butter with the chocolate. Remove from the heat and stir in the sugar. Beat in the eggs. Mix the flour, baking powder and salt in a measuring cup and stir into the chocolate mixture along with the vanilla extract. Fold in the nuts. Turn into the prepared pan and bake for 35 minutes. Cut into squares while hot, but do not remove from the pan until cooled.