AMERICA'S TEST KITCHEN OATMEAL FUDGE BARS

Steps:

• For the crust and topping: Adjust an oven rack to the middle position and heat the oven to 325 degrees. Line an 8 inch square baking pan with a foil sling and grease the foil.
• Whisk the oats, brown sugar, flour, baking powder, baking soda, and salt together in a large bowl.
• Stir in the melted butter until combined.
• Reserve 3/4 cup of the oat mixture for the topping.
• Sprinkle the remaining oat mixture into the prepared pan and press into an even layer with the bottom of a measuring cup.
• Bake the crust until light golden brown, about 8 minutes.
• Let the crust cool completely on a wire rack, about 1 hour.
• For the filling: Whisk the flour, sugar, instant espresso, and salt together in a medium bowl.
• Melt the chocolate chips and butter together in a microwave, stirring often, 1 to 3 minutes.
• Transfer the chocolate mixture to a large bowl and let cool slightly.
• Whisk in the egg until combined.
• Stir in the flour mixture until just incorporated.
• Adjust an oven rack to the middle position and heat the oven to 325 degrees.
• Spread the filling evenly over the cooled crust and smooth the top.
• Sprinkle with the reserved oat topping.
• Bake the bars until a toothpick inserted into the center comes out with a few moist crumbs attached and the filling begins to pull away from the sides of the pan, 25 to 30 minutes, rotating the pan halfway through baking.
• Let the bars cool completely in the pan, set on a wire rack, about 2 hours.
• Remove the bars from the pan using the foil, cut into squares, and serve.