- 2 cups all-purpose flour
- 1 1/2 cups old-fashioned oats (not quick-cooking)
- 1 1/2 cups packed light brown sugar
- 2 teaspoons kosher salt
- 1 1/4 cups (2 1/2 sticks) cold unsalted butter, cut into small pieces
- Nonstick cooking spray
- 1/2 cup all-purpose flour
- 1/4 cup unsweetened cocoa powder
- 1 teaspoon cinnamon
- 1/2 teaspoon chili powder
- 1/2 teaspoon kosher salt
- 2 large eggs
- 1/2 cup granulated sugar
- 1/2 cup packed light brown sugar
- 1/2 cup (1 stick) unsalted butter
- 1 cup semisweet chocolate chips
- 1/4 cup (1/2 stick) unsalted butter
- 1/3 cup heavy whipping cream
- 1/2 cup semi-sweet chocolate chips
- 1 teaspoon vanilla extract
- 1/2 cup unsweetened cocoa powder
- 3 cups sifted confectioners’ sugar
For the Oat Crust, place the flour, oats, sugar and salt in a food processor fitted with the steel blade. Pulse a couple of times to combine. Add the cold butter and pulse a few times until the mixture resembles a coarse meal. Be careful not to process too long or it will turn into a dough.
To make by hand, in a large bowl, whisk together the flour, oats, sugar and salt. Add the cold butter pieces and quickly press between your fingertips to break up the butter into the flour until the mixture resembles coarse crumbs.
Heat the oven to 350°F. Line a 9-by-13-inch baking pan with aluminum foil, allowing enough foil to overlap the edges. Spray the foil with cooking spray. Press the Oat Crust into the prepared baking pan. Set aside.
In a large bowl, whisk together the flour, cocoa powder, cinnamon, chili powder and salt. In another bowl, whisk the eggs with the granulated sugar and brown sugars until smooth.
Microwave the butter for 1 minute. Add the chocolate chips and stir until fully melted. Let cool slightly. Pour the chocolate into the egg mixture and mix well. Make a well in the flour mixture. Pour in the egg mixture and fold until fully incorporated. Pour the brownie batter onto the Oat Crust. Smooth out until even. Bake for 30 minutes.
Remove brownies from oven and let the brownies cool for 5 minutes while you make the frosting: Melt the butter in a medium saucepan over low heat. Add the heavy cream and bring to a low boil. Remove from the heat and add the chocolate chips and vanilla. Whisk until fully melted. While hot, quickly add the cocoa powder and confectioners’ sugar; beat with an electric mixer until smooth.
Frost the warm brownies with the Fudge Frosting and let them cool completely in the pan. Grab the foil handles with both hands and lift the brownies out of the baking pan. Cut into 12 squares.