1-First Step: Preparation and PreheatingBegin by preheating your oven to 350°F (175°C). This temperature is ideal for achieving golden edges while keeping the center soft and chewy. While the oven heats, prepare your baking pan by lining an 8×8-inch square pan with parchment paper. This important step prevents the bars from sticking and makes for easy cleanup. If you don’t have parchment paper, lightly grease the pan with butter or cooking spray. Ensure the paper extends slightly over the edges to create “handles” that will help you lift the bars out after baking.

2-Second Step: Mix the Dry IngredientsEmpty the entire box of cake mix into a large mixing bowl. At this stage, you can also add any dry mix-ins you plan to include, such as chocolate chips, chopped nuts, or dried fruit. Combining these ingredients before adding the wet ingredients helps distribute them evenly throughout the dough. For best results, use a whisk to break up any large lumps in the cake mix, ensuring a smooth and uniform texture in your final bars.

3-Third Step: Combine Wet and Dry IngredientsIn a separate microwave-safe bowl, melt 1/2 cup of butter. Allow it to cool slightly but remain liquid. Crack the egg into the melted butter and whisk together until well combined. Pour this mixture over the cake mix in your large bowl. Using a sturdy spoon or electric mixer on low speed, mix the ingredients together. Continue mixing until a thick, uniform dough forms. This typically takes about 2 minutes by hand or less than a minute with a mixer. The dough should be thick but pliable similar to traditional cookie dough consistency.

4-Fourth Step: Press the Dough Into the PanTransfer the dough to your prepared 8×8-inch pan. Using clean hands or the back of a spoon, press the dough evenly into the bottom of the pan. Try to maintain a consistent thickness throughout, about 1/2 to 3/4 inch thick. This ensures even baking and prevents some parts from becoming overcooked while others remain underdone. For a professional touch, you can run a straight edge (like a knife or ruler) across the top to create an even surface.

5-Fifth Step: Add Toppings (Optional)If you’re adding toppings like extra chocolate chips, sprinkles, or a swirl of peanut butter, now is the time to do so. Gently press these toppings into the surface of the dough so they adhere but don’t sink too deeply. For layered bars, sprinkle additional ingredients like mini marshmallows or caramel bits on top of the dough before baking. This creates a beautiful presentation and adds extra flavor dimensions to your cake mix bar cookies.

6-Final Step: Bake and CoolPlace the pan in your preheated oven and bake for 15-20 minutes. The exact baking time may vary depending on your oven and the specific brand of cake mix used. You’ll know the bars are done when the edges are lightly golden brown, and a toothpick inserted in the center comes out mostly clean with a few moist crumbs. Avoid overbaking, as this will result in dry, hard bars instead of soft, chewy ones.Once baked, remove the pan from the oven and place it on a wire rack to cool completely. This is crucial the bars need to set before cutting, or they may crumble. Allow at least 30-60 minutes for cooling. For best results, you can refrigerate the cooled bars for 15-20 minutes before cutting, which creates cleaner edges. After cooling, lift the bars from the pan using the parchment paper handles and cut into 16 equal squares using a sharp knife.