Cake Mix Brownies Recipe (Fudgy & Loaded with M&Ms)

If you’re craving chocolate but short on time, this recipe is your answer. The combination of melted butter, semi-sweet chocolate chips, and a cake mix creates brownies that taste completely homemade without all the fuss of measuring out flour, cocoa powder, and leavening agents.

Looking for more quick dessert recipes using cake mix? Try these Cake Mix Cookies with Sprinkles for a fun treat, or make these Easy Christmas Tree Brownie Bites for your holiday dessert table. For another chocolate fix, these Brookies Cookies combine brownies and cookies in one delicious bite.

Reasons You’ll Love This Recipe

• Super Quick: These cake mix brownies come together in just 5 minutes of prep time and bake in 25 minutes. You’ll have warm, fudgy brownies on your table in half an hour from start to finish, making them perfect for last-minute cravings or unexpected guests.
• Uses Simple Ingredients: With just a box of cake mix, butter, eggs, chocolate chips, and M&Ms, you probably have everything you need in your pantry right now. No special ingredients or trips to the store required for this easy brownie recipe.
• Kid-Friendly: These colorful M&M brownies are perfect for bake sales, birthday parties, or after-school snacks. Kids love the candy-studded top, and you’ll love how simple they are to whip up with little helpers in the kitchen.
• Perfectly Fudgy: The secret to these brownies is baking them just until the edges set while the center stays soft. This technique creates that coveted fudgy texture that makes cake mix brownies taste even better than from-scratch versions.

What Are Cake Mix Brownies?

Cake mix brownies are a simplified version of traditional brownies that use boxed cake mix as the base instead of measuring out individual dry ingredients. By adding melted butter, eggs, and mix-ins to a chocolate cake mix, you create a rich, fudgy brownie batter in minutes. This shortcut method delivers homemade-tasting brownies with minimal effort and fewer dishes to wash.

Cake Mix Brownies Ingredients

See the recipe card below for a complete list of ingredients and measurements.

• Devil’s Food Cake Mix – A 15.25-ounce box of Devil’s Food cake mix creates the chocolate base for these brownies. Duncan Hines works beautifully, but any brand of chocolate cake mix will give you delicious results.
• Salted Butter – One stick of melted salted butter adds richness and helps create that fudgy texture. The salt in the butter also balances the sweetness of the cake mix and M&Ms perfectly.
• Eggs – Two large eggs bind everything together and give structure to your brownies. Room temperature eggs incorporate more easily into the batter for a smoother consistency.
• Semi-Sweet Chocolate Chips – A full cup of chocolate chips melts into pockets of gooey chocolate throughout the brownies. You can use milk chocolate, dark chocolate, or even white chocolate chips based on your preference.
• Mini M&Ms – One cup of mini M&Ms gets divided between the batter and the topping. These colorful candies add pops of color and a slight crunch that makes each bite fun and festive.

Substitutions and Additions

• Different Cake Mix Flavors – Swap the Devil’s Food cake mix for any chocolate cake mix, fudge cake mix, or even triple chocolate cake mix for variation in chocolate intensity.
• M&M Varieties – Use peanut M&Ms, peanut butter M&Ms, or seasonal varieties like pastel Easter M&Ms or red and green Christmas M&Ms to customize these brownies for any occasion.
• Chocolate Chip Options – Replace semi-sweet chocolate chips with milk chocolate morsels, dark chocolate chunks, or chopped chocolate bars for different flavor profiles.
• Add Nuts – Stir in ½ cup of chopped pecans or walnuts to the batter for added crunch and a more traditional brownie texture.
• Peanut Butter Swirl – Drop spoonfuls of peanut butter on top of the batter before baking and swirl with a knife for peanut butter brownies.

How to Make Cake Mix Brownies (step-by-step directions)

STEP 1. Start by preheating your oven to 350 degrees F and preparing a 9×9 inch baking dish. Butter the bottom and sides of the pan, then line it with parchment paper, leaving some overhang on the sides for easy removal later. In a large mixing bowl, pour the entire box of cake mix. (Photo 1)

STEP 2. Add the melted and slightly cooled butter, and crack in both eggs. Using a wooden spoon or spatula, mix everything together until all the ingredients are fully combined and no dry pockets of cake mix remain. (Photos 2 & 3)

STEP 3. Fold in the chocolate chips and half of the mini M&Ms (about ½ cup) into the brownie batter. Stir gently until the mix-ins are evenly distributed throughout. (Photos 4 & 5)

STEP 4. Transfer the batter to your prepared baking dish and spread it evenly with a spatula, making sure it reaches all corners. Sprinkle the remaining M&Ms over the top of the batter, pressing them in gently so they stick. (Photos 6 & 7)

STEP 5. Bake the brownies in the preheated oven for 23-25 minutes. The edges should look set and pull away from the pan slightly, while the center will still appear soft but not jiggly. This is exactly what you want for fudgy cake mix brownies. (Photo 8)

STEP 6. Remove the pan from the oven and allow the brownies to cool completely in the pan before slicing. Cooling lets them set properly, which gives you cleaner cuts and the perfect fudgy texture. (Photo 9)

Recipe Tips

• Don’t Overbake – The key to fudgy brownies is removing them from the oven when they still look slightly underdone in the center. They’ll continue cooking as they cool, and overbaking leads to dry, cakey brownies instead of the fudgy texture you want.
• Cool Completely Before Cutting – Patience pays off with brownies. Let them cool fully in the pan for at least 2 hours before cutting. This allows the brownies to set and firm up, making it much easier to cut clean squares without them falling apart.
• Adjust Baking Time for Different Pan Sizes – If you’re using an 8×8 inch pan, your brownies will be thicker and need an extra 5-7 minutes of baking time. A 9×13 inch pan creates thinner brownies that bake in about 18-20 minutes.
• Use Parchment Paper – Lining your pan with parchment paper creates handles that let you lift the entire brownie slab out of the pan before cutting. This makes slicing so much easier and keeps your pan cleaner.
• Mix Until Just Combined – When stirring the batter, stop as soon as you don’t see any dry cake mix. Overmixing can make your brownies tough instead of tender and fudgy.

Storing Tips

• Storage: Allow your brownies to cool completely before storing to prevent condensation from making them soggy.
• Room Temperature: Store cake mix brownies in an airtight container at room temperature for 3-5 days. They’ll stay fresh and fudgy when kept sealed away from air.
• Refrigerator: You can refrigerate these M&M brownies in an airtight container for up to 1 week. The cold actually makes them extra fudgy, almost like eating chocolate fudge.
• Freezing: Wrap individual brownie squares in plastic wrap, then place them in a freezer-safe bag or container. Frozen brownies will keep for 2-3 months and can be thawed at room temperature when you need a quick chocolate fix.
• Reheating: For a warm brownie treat, microwave individual pieces for 10-15 seconds. The chocolate chips will get melty and gooey again, making them taste freshly baked.

Serving Suggestions

These fudgy cake mix brownies are delicious on their own, but they’re even better when served with a scoop of vanilla ice cream on top. The cold ice cream melting into the warm brownie creates the perfect dessert combination.

For a brownie sundae bar, set out these M&M brownies alongside Chocolate Brownie Cupcakes and let everyone build their own creation with whipped cream, chocolate sauce, and sprinkles. If you have extra M&Ms, try making these Easy Halloween Cookie Bars that also feature fun candy toppings. For more chocolate desserts that pair beautifully with these brownies, serve up some French Silk Brownies for an elegant dessert spread.

Recipe FAQs