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Learn how to make box brownies better! These simple tips elevate your favorite box mix brownies to the next level. If you’re craving homemade brownies but not in the mood to bake from scratch, enter these 30-minute box mix brownies. Sprinkled with flaky salt, you’ll love these fudgy, chewy brownies with crackly tops.
Box Mix Brownie Hacks
Add chocolate chips – If the brownie mix does not include chocolate chips, add up to 1 cup (170 grams) semi-sweet or dark chocolate chips. If the mix includes chocolate, add at least 1/2 cup (85 g) chocolate chips for richer brownies.
Add nuts – Add a handful of finely chopped pecans or walnuts if you love brownies with nuts.
Add mix ins – Jazz up a basic brownie mix with chopped mini peanut butter cups, white chocolate chunks, or your favorite chopped up candy bar.
Add a swirl – Swirl in spoonfuls of peanut butter or Nutella before baking. Measure out 1/3 cup (85 grams) peanut butter or Nutella in a small bowl and microwave for 10 to 15 seconds. Dollop over the top of the brownie batter and gently swirl with a toothpick. Tap pan sharply before baking.
Add salt – Flaky salt takes basic brownies (and brownie cookies) to a new level of decadence!
Add a topping – Drizzle the baked brownies with salted caramel sauce or top with vanilla ice cream and chocolate fudge sauce!
Craving more brownies? You may also love my easy cocoa powder brownies, fudgy brown butter brownies, or caramel-topped turtle brownies!
Ingredient Notes
Boxed brownie mix typically calls for vegetable oil. Using butter instead of oil is the secret to brownies that taste like they’re baked from scratch.
Most brownie mixes call for one whole egg. Adding the egg plus an extra egg yolk gives brownies an ultra fudgy texture.
To intensify the chocolate flavor, I like to add a bit of espresso powder – instant is great because it dissolves easily in the brownie batter.
How to Make the Best Box Brownies
Preheat oven to 350°F and line an 8-inch square metal baking pan with parchment paper letting a 2-inch overhang extend over sides of pan.
Combine melted butter, instant espresso powder, vanilla, egg, and egg yolk in a large bowl. Whisk until smooth and combined. Add box brownie mix to the bowl.
Fold in brownie mix with a spatula just until combined and no flour streaks remain. Expect a thick batter!
Add chocolate chips and fold in to the batter. Don’t skip the additional chocolate – the added sugar helps the brownies form a shiny, crinkly top as they bake!
Scrape brownie batter into prepared pan and smooth the top. Gently tap the pan once to remove air bubbles.
Bake these brownies until just set, about 25 to 26 minutes. A toothpick inserted in the center should come out with a few fudgy crumbs attached. Sprinkle the tops of the brownies with flaky salt.
Let the brownies cool completely, then cut into squares with a sharp knife. Store brownies in an airtight container at room temperature.
Favorite homemade brownie recipes:
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How to Make Box Mix Brownies Even Better
- Prep Time: 5 minutes
- Cook Time: 25 minutes
- Total Time: 30 minutes
- Yield: 12 to 16 brownies
- Category: Dessert
- Method: Bake
- Cuisine: American
Description
Learn how to make box brownies better! These tips elevate your favorite box mix brownies to the next level. You’ll love these fudgy, chewy brownies with crackly tops.
Ingredients
- 6 Tbsp (84 g) unsalted butter, melted
- 1 tsp (8 g) instant espresso powder
- 1 1/2 tsp (6 g) vanilla extract
- 1 large egg (50 g), at room temperature
- 1 large egg yolk (17 g), at room temperature
- 1 18 oz (502 g) box brownie mix
- 1/2 cup (85 g) semisweet chocolate chips
Topping
- flaky salt (such as Maldon)
Instructions
- Preheat oven to 350°F and line an 8-inch square metal baking pan with parchment paper.
- Make brownies: Combine melted butter, instant espresso powder, vanilla, egg, and egg yolk in a large bowl. Whisk until smooth and combined. Add box brownie mix to the bowl and fold in with a spatula just until combined and no flour streaks remain (batter will be thick). Fold in chocolate chips.
- Scrape brownie batter into prepared pan. Use a piece of parchment paper to press batter evenly into pan and smooth the top. Gently tap pan once to remove air bubbles.
- Bake brownies for 25 to 26 minutes, until the top is set and a toothpick inserted in the center comes out with a few crumbs attached. Remove from oven and place on a wire rack to cool completely. Sprinkle the tops of the brownies with flaky salt.
- Lift parchment and place brownies on a cutting board. Cut into squares with a sharp knife. Store leftover brownies in an airtight container at room temperature.
Notes
Boxed brownie mix: Use your favorite brownie mix that’s approximately 18 oz (502 grams). For a larger 20 oz brownie mix (567 grams), I recommend increasing the butter to 1/2 cup (112 grams).
Chocolate chips: If the box brownie mix does not include chocolate chips, add up to 1 cup (170 grams) semisweet or dark chocolate chips. If the mix includes chocolate, add at least 1/2 cup (85 g) chocolate chips.
Flaky salt: I use Maldon Sea Salt Flakes.
Peanut butter or Nutella swirl: Measure out 1/3 cup (85 grams) peanut butter or Nutella in a small bowl and microwave for 10 to 15 seconds. Dollop over the top of the brownie batter and gently swirl with a toothpick. Tap pan sharply before baking.
Bake time: May vary based on the size of your brownie mix and any swirls or additions. Start testing for doneness after 25 minutes, and continue to test every 2 minutes until a toothpick emerges with a few moist crumbs attached.
Can brewed coffee be used instead of espresso powder? If so, how much?
Hi Jane, I recommend instant espresso because it adds the coffee flavor without adding additional moisture. If you want to try brewed coffee, I’d start with about 2 tablespoons and see how the brownie texture turns out once baked.
I am so glad I came across your brownie recipe I used butter instead of oil added espresso powder and swirl ls peanut butter and chocolate chip morsels. But then I had a large Hershey chocolate bar after I pulled from oven it melted on top off brownies and with spatula I spread to cover the brownies let’s not got the chopped walnuts topping. Came home from work and kids didn’t save me one brownie that’s saying something must of liked them👍
Thanks so much for sharing, Lisa!
Came out amazing! Instead of standard melted butter, I took it the extra step and made brown butter. The nutti-ness of the brown butter and butter espresso really added depth and helped the brownie be not too sweet, which was perfect. And super easy using a box mix!
Brown butter is always a good idea. 🙂 Thank you, Kaelan!
Delicious fudgy brownies. This recipe really elevates a box brownie
Thanks for your feedback, Sue!
Super delicious. I used this recipe to make my brookie ( brownie and cookie mix). It was amazing. I would have never thought to add espresso to chocolate but it really made the flavor pop. The brookie came out so well! The brownie was the right amount of sweet, rich, buttery and quite decadent. Thank you!
That’s great to hear, thank you Mariah!
The batter was extremely thick. You don’t add any water? I added a splash just so I could stir it. Spread it in the pan and now it’s in the oven…fingers crossed. You’ve never steered me wrong before!
Hi Ellen, it is a thick batter so I think you’re on the right track. 🙂
Love the tips to use butter and an extra egg yolk. The espresso powder really brings out the chocolate flavor, and the added chocolate makes all the difference.
Thanks Jen, glad to hear that you found the tips helpful!
Cinnamon is also a good add in as well as a dash cayenne pepper.
Happy baking
I agree, Joan! Great ideas to add some spice. 🙂
These brownies are so good! Just the right amount of chewy, fudgy, and chocolatey. Love how easy they are too.
Thanks so much, Sue! Glad you tried these.
Add cream cheese!
Hi Devah, that’s a great idea too!