If you’re looking for a quick, crowd-pleasing dessert that’s bursting with colorful M&Ms and melty chocolate, then you’re in the right place! This 30 Minute M&M Cookie Bars Recipe is one of my all-time favorites because it’s super easy, bakes up thick and chewy, and fills your kitchen with the kind of aroma that makes everyone gather around. Whether you’re making a last-minute treat or prepping for a party, these bars hit the spot every time.
Why You’ll Love This Recipe
- Speedy & Simple: You’ll have these cookie bars ready in just about 30 minutes – perfect for when time is tight but you want big flavor.
- Perfectly Chewy Texture: Unlike some cookie bars that turn cakey, these stay thick and chewy thanks to the right balance of ingredients.
- Loaded With Candy & Chocolate: My family goes crazy for the mix of M&Ms and dark chocolate chunks in every bite.
- Easy Cleanup: Using a parchment paper sling means no scraping or sticking, making cleanup a breeze.
Ingredients You’ll Need
This recipe nails the balance between buttery richness and just enough sugar to keep it chewy—not too sweet, and with pops of chocolate and M&Ms for texture and flavor. I recommend using unsalted butter so you control the saltiness perfectly, and dark chocolate to deepen the candy’s sweetness.
- Unsalted Butter: Melting the butter first helps the bars stay nice and chewy.
- Light or Dark Brown Sugar: This adds moisture and helps create the perfect chewiness.
- Granulated Sugar: For a subtle crunch and balance to the brown sugar.
- Egg Yolks: Using just yolks (no whites) results in a fudgier texture that I love.
- Vanilla Bean Paste or Extract: Vanilla is what makes these taste so rich and warm.
- All-Purpose Flour: The base that holds everything together – no fancy flours needed!
- Baking Powder: Just a little to help the bars rise perfectly without getting cakey.
- Salt: Essential for balancing the sweetness and enhancing flavor.
- M&Ms: The star candy that brings vibrant colors and sweet crunch.
- Dark Chocolate, Chopped: Adding chopped chocolate gives gooey pockets between the bars.
Variations
One of the things I love about this 30 Minute M&M Cookie Bars Recipe is how easy it is to make your own. Over time, I’ve swapped out ingredients or added extras to fit what I had on hand or my family’s preferences.
- Nutty Twist: I sometimes throw in chopped walnuts or pecans for a little crunch and extra depth.
- Peanut Butter Version: Adding a few tablespoons of peanut butter makes the bars irresistible and pairs beautifully with M&Ms.
- White Chocolate Swap: For a sweeter, creamier flavor, substitute white chocolate chunks instead of dark chocolate.
- Gluten-Free: I’ve tried this with a gluten-free all-purpose blend and it still worked great, just watch your baking time.
How to Make 30 Minute M&M Cookie Bars Recipe
Step 1: Prepare Your Pan and Preheat
First things first, preheat your oven to 350°F (180°C) and prep an 8-inch square baking pan. Grease it well and line it with parchment paper, leaving extra overhang on the sides—this “sling” is your best friend for easy removal later. Secure the parchment with binder clips if you have them to keep everything in place. I learned the hard way that if you don’t line your pan properly, cleanup can be a hassle!
Step 2: Whisk Together the Wet Ingredients
In a medium bowl, combine the melted (and cooled) butter with brown sugar, granulated sugar, egg yolks, and vanilla. Whisk them together vigorously until the mixture thickens and lightens in color slightly—it usually takes about 2-3 minutes with a handheld mixer, or use your arm power if you’re ready for a mini workout! This step is crucial to get that chewy texture, so don’t skip on whipping the mixture.
Step 3: Add Dry Ingredients and Mix
Next, sift in the flour, baking powder, and salt to the wet mix. Fold everything together gently using a spatula just until you see a few streaks of flour left. Overmixing here can make the bars tough, so patience is key. I usually stop when I can’t see big lumps of flour, trusting that any little streaks will bake out nicely.
Step 4: Stir in the M&Ms and Chocolate
Fold in the M&Ms and dark chocolate chunks carefully to distribute them evenly without breaking the candies. You want vibrant speckles of candy throughout every bite. I always save a handful of M&Ms to sprinkle on top before baking for that extra pop of color and fun texture.
Step 5: Bake Until Golden
Scrape the dough into your prepared pan and press it down smoothly with an offset spatula. Bake for 20-22 minutes until the top is golden and set. The edges will look just a little firmer but don’t overbake — you want soft and chewy, not dry. If you like your edges crispy, you can leave it in for a couple extra minutes, but keep a close eye! Pro tip: The bars will continue to firm up as they cool, so don’t worry if they seem a bit soft right out of the oven.
Step 6: Cool, Slice, and Enjoy
Allow the cookie bars to cool completely in the pan on a wire rack. Using the parchment sling, carefully lift the whole slab out. Slice into 12 squares with a sharp knife — and just like that, you have perfect chewy, colorful cookie bars ready to devour. I love wrapping leftovers individually so they stay fresh for snacking all week.
Pro Tips for Making 30 Minute M&M Cookie Bars Recipe
- Butter Melting Magic: Weigh your butter after melting to ensure precision—even adding a tiny bit extra if needed really helps the texture.
- Don’t Skip Whisking: Whipping the wet ingredients thoroughly traps air and lightens the batter, making the bars chewy and tender rather than dense.
- Parchment Paper Sling: This simple trick makes removing the cookie bars seamless—no crumbling or smashing.
- Watch Baking Time: Overbaking leads to dry bars—pull them out when edges are just set but the center is still soft.
How to Serve 30 Minute M&M Cookie Bars Recipe
Garnishes
I usually keep it simple and top the bars with a sprinkle of extra M&Ms before baking for that bright, colorful look. Sometimes I dust a very light sprinkle of flaky sea salt after baking—it highlights the chocolate and balances the sweetness beautifully.
Side Dishes
These cookie bars pair wonderfully with a scoop of vanilla ice cream or a glass of cold milk—classic combos that never fail. For parties, I like adding fresh berries on the side to brighten the plate visually and add a little freshness.
Creative Ways to Present
I’ve served these bars at birthday parties in decorative trays lined with colorful paper and small festive flags poked into each square. They’re an instant hit! For holiday gatherings, swapping M&Ms for seasonal colors adds even more charm without extra effort.
Make Ahead and Storage
Storing Leftovers
Store your leftover cookie bars in an airtight container at room temperature. I’ve found they stay perfectly chewy and fresh for up to three days. Just make sure to keep them away from humid spots so they don’t get too soft or sticky.
Freezing
When I want to make a batch ahead or save extras, I wrap individual bars tightly in plastic wrap and then place them in a freezer-safe bag. Frozen, they last for up to two months and defrost quickly on the counter or in the fridge overnight.
Reheating
To bring back that warm just-baked feeling, pop a cookie bar in the microwave for 10-15 seconds. It softens the chocolate and revives the chewy texture beautifully without drying out. If you prefer, a quick 5-minute zap in a 300°F oven works great too.
FAQs
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Can I use regular chocolate chips instead of chopped chocolate?
Absolutely! Regular chocolate chips will work just fine and melt similarly during baking. I prefer chopping a bar of dark chocolate because it melts into gooey pockets that feel more indulgent, but chocolate chips make the recipe even easier.
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Can I substitute all the sugars with brown sugar only?
You can, but using a mix of brown and granulated sugar gives the cookie bars a better texture — brown sugar keeps it chewy while granulated sugar adds a slight crispness and lightness. Using all brown sugar might make your bars softer and a bit denser.
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Do I have to use egg yolks only?
For the best chewy texture, the recipe calls for egg yolks only, which adds richness and moisture without extra structure. If you try using whole eggs, the bars may turn out cakier and less tender.
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Can I make the 30 Minute M&M Cookie Bars Recipe dairy-free?
Yes! Substitute the butter with a good-quality dairy-free margarine or coconut oil (solid, not melted). Keep in mind this might slightly change the texture and flavor, but it still makes delicious bars.
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How do I cut the bars neatly without crumbling?
Let the bars cool completely before slicing, ideally at room temperature or chilled for about 30 minutes. Use a sharp, serrated knife and clean it between cuts to get clean edges. I sometimes warm the knife under hot water and dry it off for smoother slicing.
Final Thoughts
This 30 Minute M&M Cookie Bars Recipe has become my go-to whenever I need a fast dessert that feels homemade and special. It’s such a joy to share with friends and family because everyone loves the comforting chewy texture paired with sweet bursts of candy and chocolate. I’m confident once you try this, you’ll keep it in your recipe rotation too. So grab that melted butter and those M&Ms, and enjoy baking something sweet that’s as fun to make as it is to eat!
Print
30 Minute M&M Cookie Bars Recipe
- Prep Time: 10 minutes
- Cook Time: 25 minutes
- Total Time: 35 minutes
- Yield: 12 servings
- Category: Dessert
- Method: Baking
- Cuisine: American
Description
These 30 Minute M&M Cookie Bars are a deliciously thick and chewy treat, packed with colorful M&Ms and rich dark chocolate chunks. Perfect for when you want all the flavor and texture of a classic cookie but baked into convenient bar form. They are quick to prepare, baked to a golden brown with slightly crispy edges, and make a fantastic snack or dessert for any occasion.
Ingredients
Wet Ingredients
- 100g unsalted butter, melted and cooled (re-weigh after melting and add a little extra butter if needed)
- 120g light or dark brown sugar
- 45g granulated sugar
- 2 large egg yolks, at room temperature (about 45g egg yolks)
- 1 tsp vanilla bean paste or vanilla extract
Dry Ingredients
- 135g all-purpose flour
- ¼ tsp baking powder
- 2g salt (½ tsp kosher salt)
Add-ins
- 180g M&Ms plus a few more for topping, optional
- 85g dark chocolate, chopped
Instructions
- Preheat oven and prepare pan: Preheat your oven to 350°F (180°C). Grease and line an 8-inch (20cm) non-stick baking pan with parchment paper, leaving the parchment extending over the sides to create a sling for easy bar removal. Secure with binder clips if needed.
- Mix wet ingredients: In a medium bowl, combine the melted butter, brown sugar, granulated sugar, egg yolks, and vanilla. Whisk vigorously by hand or with a handheld electric mixer until the mixture thickens and lightens slightly in color.
- Add dry ingredients: Sift in the flour, baking powder, and salt. Fold these gently into the wet mixture using a spatula until just a few flour streaks remain. Avoid overmixing for tender bars.
- Incorporate M&Ms and chocolate: Fold in the M&Ms and chopped dark chocolate with the spatula until evenly distributed throughout the dough.
- Press dough into the pan: Transfer the dough into the prepared pan and smooth the surface with an offset spatula. Optionally, press a few extra M&Ms on top for decorative effect.
- Bake: Bake the cookie bars for 20 to 22 minutes, or until the top is golden brown and set, and the edges are starting to firm up. For crispier edges, bake a bit longer as desired.
- Cool and serve: Remove the pan from the oven and cool on a wire rack. Once cooled, lift the bars out using the parchment sling and cut into 12 pieces with a sharp knife.
- Storage: Store the cookie bars in an airtight container at room temperature for up to 3 days to maintain freshness.
Notes
- These cookie bars are thick, chewy, and packed with chocolate and M&Ms, combining the best of cookie flavor and bar convenience.
- Ensure the egg yolks are at room temperature for better mixing and texture.
- Use binder clips to secure parchment paper for easy bar removal from the pan.
- Baking times may vary slightly depending on your oven; keep an eye on the edges to prevent overbaking.
- For a nuttier twist, you could add chopped nuts alongside the chocolate.
Nutrition
- Serving Size: 1 bar (approx. 1/12th of recipe)
- Calories: 260 kcal
- Sugar: 18 g
- Sodium: 110 mg
- Fat: 13 g
- Saturated Fat: 7 g
- Unsaturated Fat: 5 g
- Trans Fat: 0 g
- Carbohydrates: 30 g
- Fiber: 1.5 g
- Protein: 3 g
- Cholesterol: 55 mg
