SUPER Fudgy Brownies from a Box Mix

In today’s post: Learn how to make incredible fudgy brownies from a box mix – including homemade fudge frosting!

I make most of my baked goods from scratch, but there are times when boxed mixes can save the day. I’ve made every kind of cake mix cookie under the sun, and they’re good! And I actually really like boxed brownie mixes IF you know how to hack them for maximum fudginess. I think my mom originally got today’s “recipe” from a friend 35 years ago, and they’ve been a hit ever since. A few simple changes turns the boxed brownies into the fudgiest things you’ve ever tasted, and a quick homemade fudge frosting takes them over the top.

I’ve taken these to church potlucks, extended family gatherings, and given them as Christmas gifts, and I always get rave reviews. People think they came from a fancy bakery, and they can’t believe they started with the convenience of a boxed brownie mix!

How to Make Fudgy Brownies from a Box Mix

If you want truly fudge brownies from a box mix, you need to make a couple simple adjustments. This won’t make it take any longer to stir up your brownies – it’s just as easy as following the box directions – but the results are phenomenal.

First, use 2 eggs instead of 3. Most standard brownie mixes call for 3 eggs, which make the brownies rise higher and give them a cake-like texture. For fudgy brownies, just use two eggs.

Next, use melted butter instead of oil. This adds an extra rich flavor and helps the fudge texture.

Cook the brownies in a 9×9 pan instead of a 9×13. This recipe calls for the “family size” brownie box that says it makes a 9×13 pan. But using a 9×9 pan instead gives taller brownies that look more professional. Because this recipe is rich, you’ll still get 16 brownies from a 9×9 pan. But if you need even more you can double it and bake it in an 11×17 high sided baking sheet (jelly roll or half sheet pan).

Do not overbake the brownies. This one is important! For a really great texture, you’ll want to take the brownies out when a toothpick inserted near the center comes out mostly clean – a few crumbs are just fine. Different type of pans cook differently, so you’ll want to use the cook time as a guide but be sure you are checking a few minutes early. I think brownies cook best/most evenly in metal pans, so that’s what I recommend. Using a glass pan or insulated baking sheet (for a double batch) may mean you need a few more minutes of cook time.

We’re also going to add chocolate chips to the brownie batter AND top the baked brownies with a simple fudge frosting for maximum richness and fudginess!

Finally, for truly fudge brownies you must let them cool completely before serving. In fact, most brownies actually taste better the day after baking! That’s because we take them out of the oven when they are just set, and they really need at least 4-6 hours to set up and fudgify. Can you eat them before that? Of course. But they’ll taste better if you wait!

One last note: I like to line my 9×9 pan with parchment paper so that once the brownies are completely cooled I can use the paper to lift the brownies out of the pan before slicing. Then use a long sharp knife or a large pizza cutter to slice into squares. A plastic knife also works really well!

Fudgy Brownies from a Box Mix Recipe

Let’s Make

Fudgy Brownies from a Box Mix

Serves: 16

Prep Time: 15 mins

Cook Time: 28 mins

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This recipe turns a box mix into the fudgiest brownies you've ever tasted! The simple homemade fudge frosting takes them over the top.

Ingredients

Brownies

• 1 18 oz Boxed Brownie Mix family size, for a 9x13 pan
• 2 Eggs
• 1/2 cup Butter melted
• 1/4 cup Water
• 1 cup Semi Sweet Chocolate Chips

Fudge Frosting

• 5 tbsp Butter
• 1/2 cup Baking Cocoa
• 1/4 cup Water
• 1/8 tsp Salt
• 1 tsp Vanilla
• 2 cups Powdered Sugar

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Instructions

• Preheat the oven to 350 degrees. Line a 9x9 baking sheet with parchment paper.
• In a bowl, stir together the brownie mix, melted butter, eggs, and water. Stir in chocolate chips. Batter will be thick.
• Spread batter into 9x9 pan. Bake approx 26-30 minutes, or until a toothpick inserted near the center of the brownies comes out mostly clean (a few crumbs are ok). If the toothpick comes out covered in chocolate, that means you've hit a chocolate chip, so test again in another spot.
• During the last five minutes of bake time, mix up the fudge frosting. In a medium saucepan, melt the butter over medium heat.
• Take the saucepan off the heat and whisk in the cocoa, water, vanilla, and salt. Mixture will be thick and may look a little grainy.
• Whisk in the powdered sugar, 1/2 cup at a time. Continue whisking until frosting is smooth and glossy.
• Poor frosting on hot brownies and spread out if needed. Allow brownies to cool COMPLETELY, 4-6 hours, before serving.

Tips

Please note that many things affect cooking time for brownies, including your oven temperature and the type of pan you bake them in. Use the suggested time as a guide and watch the brownies carefully.

Recipe may be doubled and baked in an 11x17 high sided cookie sheet (aka jelly roll or half sheet pan).

I prefer a Duncan Hines brownie mix for this recipe.

Course: Dessert

Cuisine: Brownies