This post may contain affiliate links. Please see my disclosure policy.
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 (just like my reader-favorite salted brownie cookies!), 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 to a new level of decadence!
Add a topping – Drizzle the baked brownies with salted caramel sauce, butterscotch sauce, or top with vanilla ice cream and chocolate fudge sauce!
Don’t overbake – The key to fudgy box brownies is to bake just until set (a toothpick or tester should emerge with a few fudgy crumbs).
Craving more brownies? You may also love my easy cocoa powder brownies, fudgy brown butter brownies, or caramel-topped turtle brownies!
Key Ingredients
Here’s what you need to make box brownies taste homemade:
- Butter – Boxed brownie mix typically calls for vegetable oil. Using butter is the secret to brownies that taste like they’re baked from scratch (use unsalted butter to control the salt level).
- Espresso powder – Intensifies the chocolate flavor. I use Starbucks VIA because it dissolves easily in the brownie batter.
- Vanilla extract – Pure vanilla extract adds rich flavor to brownies.
- Eggs – Most brownie mixes call for one whole egg. Adding one large egg plus an extra egg yolk gives brownies an ultra fudgy texture.
- Chocolate Chips – Even if your brownie mix contains chocolate, plan to add chocolate chips. The additional sugar from the chocolate chips creates a shiny, crackly top as the brownies bake.
- Boxed Brownie Mix – Use your favorite brownie mix that’s approximately 18 oz (502 grams).
- Flaky salt – Elevates every chocolate recipe! I love Maldon flaky salt.
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!
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, 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:
- Ultimate Crinkle Brownies
- Decadent Triple Chocolate Brownies
- Salted Caramel Turtle Brownies
- Peanut Butter Cup Brownies
- Fudgy Brown Butter Brownies
Did you try these Better Box Brownies? Let me know by leaving a comment and rating below!
PrintHow 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.
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!