This recipe has been featured as the base of many brownie recipes, including Milky Way Brownies and Twix Bar Brownies.

Oreo Chunk Brownies
Yield: 40 brownies (or more!)
Prep Time: 30 min
Cook Time: 30 min
This fudgy brownie recipe turns out a nice, sturdy brownie- perfect for swirling in chunks of candy or cookies.
Ingredients:
1 pound (4 sticks) unsalted butter
1 pound semi-sweet chocolate (or chocolate chips)
6 ounces unsweetened chocolate, chopped
2 Tablespoons instant espresso powder
7 large eggs
2 Tablespoons vanilla extract
2 1/4 cups granulated white sugar
1 1/4 cups all-purpose flour, divided
1 Tablespoon baking powder
1 teaspoon salt
4 cups (40 cookies) broken Oreos (1 package)Directions:
1. Preheat oven to 350°F. Butter and flour 12x18x1-inch pan. Line with foil or parchment that hangs over the sides for ease in getting them out (butter the foil/parchment).
2. In a heatproof, medium-bowl set over a saucepan of simmering water, heat butter, and chocolates until melted and smooth; cool slightly.
3. In a large bowl, whisk together the eggs, espresso powder, vanilla and sugar. Stir the egg mixture into the slightly cooled chocolate mixture. Cool to room temperature.
4. In a medium bowl, sift together 1 cup of flour, baking powder, and salt, then add to batter. In a small bowl, stir Oreos and remaining 1/4 cup flour. Stir cookies into chocolate mixture. Then pour into prepared baking pan and smooth top with a rubber spatula.
5. Bake for 25 to 35 minutes, or until toothpick inserted in center comes out clean with a few crumbs attached; do not overbake! Let cool completely, then cover tightly and chill overnight. Chilled brownies are easier to cut. Dump the chilled brownie pan onto a large cutting board, peel off the foil and cut into squares.
Tips:
*These taste even better the second day.
*Try adding in different kinds of cookies or candy. I'm thinking Girl Scout Thin Mints next time!Source: RecipeGirl.com (Adapted from Ina Garten)