Brownie Base
1 cup unsalted butter
14 ounces semisweet chocolate, coarsely chopped
4 ounces unsweetened chocolate, coarsely chopped
½ cup packed dark brown sugar
½ cup packed light brown sugar
½ cup granulated sugar
5 large eggs, lightly beaten
1 tablespoon vanilla extract
¼ cup milk
1½ cups unbleached, all-purpose flour
1 teaspoon salt
1½ cups coarsely chopped walnuts, toasted
Chocolate Drizzle
1/3 cup heavy (whipping) cream
3 ounces bittersweet chocolate, finely chopped
2 ounces semisweet chocolate, finely chopped
Heat oven to 350 degrees F. Combine the butter and chocolates in a large saucepan over low heat, stirring until mixture is melted and smooth. Whisk in sugars, eggs, vanilla extract and milk, blending until smooth. Add flour and salt just until mixture is combined, stir in nuts and spread into 13 x 9-inch baking pan lined with greased parchment paper. Bake for 25 to 30 minutes or so. Cool pan completely on a wire rack. Top with crushed Oreos.
For the drizzle, bring cream to a simmer in a medium saucepan. Remove pan from heat and add chocolates, whisk until smooth and cool until thickened. Pour over brownies, and cool in the refrigerator until firm before cutting into bars.
