If you’re looking for a cookie bar recipe that feels festive, comforting, and just downright addictive, you’re going to love this one. The Brown Butter M&M Cookie Bars Recipe is my go-to when I want something that’s both chewy and rich, with that nutty depth from browned butter—and let’s not forget those colorful M&M’s bringing that perfect pop of fun. When I first tried this recipe, it instantly became a family favorite, and I can’t wait for you to try it too!
Why You’ll Love This Recipe
- Rich Brown Butter Flavor: Browning the butter brings a deep, nutty taste that elevates these cookie bars to a new level.
- Perfect Texture: Soft, chewy in the center with a slight crisp around the edges—it hits all the cookie textural notes.
- Festive & Fun: Those Christmas M&M’s add bursts of colorful sweetness that make these bars really pop for any occasion.
- Easy to Make: No fancy equipment or complex steps, just straightforward baking that you’ll enjoy every step of.
Ingredients You’ll Need
These ingredients come together so perfectly—the brown butter adds richness, M&M’s add crunch and color, and a hint of flaky sea salt seals the deal by balancing the sweetness.
- Salted Butter: Browning this really unlocks the best flavor, so don’t rush it—it should smell nutty and golden.
- Dark Brown Sugar: Adds moisture and a caramel-like depth that’s key for chewy texture.
- Granulated Sugar: Balances the brown sugar’s moisture with some crunch.
- Eggs: Make sure they’re at room temperature for the best blend and structure.
- Vanilla Extract: A must-have for that warm, familiar sweetness.
- All-Purpose Flour: The backbone that holds everything together.
- Baking Soda: For gentle leavening to keep these bars light and tender.
- Kosher Salt: Enhances flavor without overpowering.
- Semi-Sweet Chocolate Chips: Melts slightly into pockets of gooey goodness throughout the bars.
- Christmas M&M’s: Colorful and crunchy festive candies that brighten every bite.
- Hershey’s Milk Chocolate Kisses: Halved and placed on top, they gently melt in the oven for extra chocolatey flair.
- Flaky Sea Salt: Sprinkled last to give that perfect sweet-salty contrast and a lovely crunch.
Variations
I love how flexible this Brown Butter M&M Cookie Bars Recipe is. Once you nail the basics, it’s fun to play around with add-ins to suit your mood or occasion.
- Add Nuts: I often toss in chopped pecans or walnuts for an extra crunch and nutty dimension—it’s irresistible.
- Swap the M&M’s: Try peanut butter or crispy M&M’s for a fun twist on texture and flavor.
- Use Dark Chocolate Chips: For a slightly less sweet, more sophisticated chocolate flavor that adults will especially appreciate.
- Make It Vegan: I haven’t tested this extensively, but swapping butter for vegan margarine and eggs for flax eggs might do the trick.
How to Make Brown Butter M&M Cookie Bars Recipe
Step 1: Brown the Butter to Perfection
Start by melting your butter in a skillet over medium heat. Keep an eye on it as it melts and begins to foam. Soon, you’ll see it turning golden and smell that amazing nutty aroma—that’s when your brown butter is ready (usually about 3-4 minutes). This step is key because it adds such depth of flavor; don’t skip it! Once browned, pour it into a bowl and pop it in the freezer for 10-15 minutes to cool off but not harden.
Step 2: Mix the Dough
Preheat your oven to 350°F and line a 9×13-inch pan with parchment paper for easy removal. In a large bowl, beat together the browned butter with your sugars until smooth and well combined—this helps with a tender crumb. Add the eggs one at a time, mixing well after each, then stir in the vanilla. Next up, sift together flour, baking soda, and salt in a separate bowl, then gradually add these dry ingredients to your wet mix. Stir in the M&M’s last so they don’t get crushed.
Step 3: Layer and Bake
This is where the magic happens! Scoop out about a cup of dough and set it aside. Mix chocolate chips into the remaining dough, then press that mixture evenly into your pan. Now press the reserved dough on top to mostly cover, leaving a bit of a patchwork look—that’s how I get extra chewy bites with a variety of flavors. If you want, sprinkle some extra M&M’s on top for extra pizzazz. Bake for about 18-22 minutes; you want the edges golden but the center still a little soft. It’s okay if it looks slightly underdone—that means chewy perfection.
Step 4: Add the Finishing Touches
Right after you pull the bars out of the oven, gently place halved Hershey’s Kisses all over the top. Pop it back in the oven for just 1-2 minutes until those kisses melt slightly. Once out, sprinkle with flaky sea salt—that little salty crunch makes these bars irresistible. Let them cool a bit or dive in warm—you really can’t go wrong here!
Pro Tips for Making Brown Butter M&M Cookie Bars Recipe
- Don’t Skip the Chill: Cooling the browned butter before mixing helps prevent your eggs from scrambling and keeps your dough just right.
- Watch the Bake Time Closely: Everyone’s oven is a bit different, so start checking at 18 minutes to keep that soft center.
- Parchment Paper is Your Friend: Line your pan well for easy removal and cleaner edges.
- Flaky Sea Salt for Balance: Adding this at the end amps up the flavor and adds a gourmet touch you won’t want to skip.
How to Serve Brown Butter M&M Cookie Bars Recipe
Garnishes
I like to add just a little extra flaky sea salt right before serving, especially if I’ve stored the bars in the fridge. Sometimes, I’ll pop on a couple mini M&M’s for extra color and crunch because, why not? It instantly makes the bars look festive and inviting.
Side Dishes
These cookie bars pair beautifully with a cold glass of milk (classic for a reason!), or for a grown-up touch, a cup of rich coffee or even a cup of hot cocoa topped with whipped cream.
Creative Ways to Present
For holiday parties, I like to cut them into fun shapes using cookie cutters on the bars after they cool just a bit—they make perfect little gifts or stocking stuffers. You could also layer them in a pretty tin with parchment paper between layers for a charming gift that’s sure to wow.
Make Ahead and Storage
Storing Leftovers
I keep leftovers in an airtight container at room temperature for up to 5 days—it preserves the chewy texture nicely. If your kitchen is warm, a cool spot or fridge is fine, but I recommend warming the bars slightly before enjoying.
Freezing
Freezing these bars works well—I slice them first, then freeze in a single layer on a baking sheet. Once frozen solid, I transfer the bars to a freezer bag for up to 2 months. It’s convenient for grabbing a sweet treat whenever you want!
Reheating
To revive the bars, I usually microwave a slice for about 15 seconds or warm them briefly in the oven wrapped in foil at 300°F. This brings back that melty, soft texture that makes them so irresistible.
FAQs
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Can I use unsalted butter instead of salted butter in this recipe?
Yes! If using unsalted butter, I recommend adding a pinch more salt (about 1/4 teaspoon) to compensate for the missing saltiness. The salt level helps balance sweetness and enhance flavors.
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What if I don’t have Hershey’s Kisses—can I skip them?
Absolutely. The kisses add a lovely melty chocolate finish on top, but if you don’t have them, just skip that step or add a handful of extra chocolate chips on top before baking. It won’t change the fundamental deliciousness.
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How do I know when the Brown Butter M&M Cookie Bars Recipe is done baking?
The edges should look golden brown while the center remains soft and slightly underbaked—that’s the sweet spot for chewy bars. They’ll firm up a bit as they cool, so don’t overbake.
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Can I use regular M&M’s instead of Christmas M&M’s?
Yes, you can swap in any M&M’s you like! The Christmas ones just add a little seasonal color, but the taste and texture are the same with regular, peanut, or any other variety.
Final Thoughts
Honestly, this Brown Butter M&M Cookie Bars Recipe has become one of those recipes I always keep in my back pocket for when I want to impress guests or just indulge myself (and my family). The combination of that toasty, brown butter flavor with melty chocolate and M&M crunch is pure joy in every bite. If you try it, don’t be surprised if it disappears fast—and if you have leftovers, warm them up and savor every gooey moment. I genuinely hope this recipe becomes a favorite in your kitchen too!
Print
Brown Butter M&M Cookie Bars Recipe
- Prep Time: 15 minutes
- Cook Time: 20 minutes
- Total Time: 45 minutes
- Yield: 22 bars
- Category: Dessert
- Method: Baking
- Cuisine: American
Description
These Brown Butter Christmas M&M Cookie Bars combine the rich nuttiness of browned butter with festive Christmas M&M’s and melty chocolate chips for a fun and delicious holiday treat. Soft and chewy with a slight crunch from flaky sea salt on top, these bars are perfect for sharing during the holidays or as a sweet gift. The layered dough approach adds extra texture and chocolatey goodness, making these cookie bars a standout dessert for Christmas celebrations.
Ingredients
Butter and Sugars
- 2 sticks (1 cup) salted butter
- 3/4 cup packed dark brown sugar
- 1/4 cup granulated sugar
Wet Ingredients
- 2 large eggs, at room temperature
- 1 tablespoon vanilla extract
Dry Ingredients
- 2 1/4 cups all-purpose flour
- 3/4 teaspoon baking soda
- 1/2 teaspoon kosher salt
Add-ins and Toppings
- 1 cup semi-sweet chocolate chips
- 1 cup Christmas M&M’s (or more!)
- 10-12 Hershey’s Milk Chocolate Kisses, halved
- Flaky sea salt, for sprinkling
Instructions
- Brown the Butter: Add the butter to a skillet over medium heat. Cook, stirring occasionally, until it begins to turn golden brown and smells nutty, about 3-4 minutes. Remove from heat and immediately transfer to a heatproof bowl. Chill in the freezer for 10-15 minutes to cool but not harden.
- Prepare Baking Dish and Oven: Preheat your oven to 350°F (175°C). Line a 9×13 inch baking pan with parchment paper to prevent sticking and for easy removal of the cookie bars.
- Combine Sugars and Butter: In a large mixing bowl, beat together the cooled browned butter, dark brown sugar, and granulated sugar until completely combined and smooth.
- Add Eggs and Vanilla: Incorporate the eggs one at a time, beating well after each addition until fully combined. Stir in the vanilla extract.
- Mix Dry Ingredients: Add the all-purpose flour, baking soda, and kosher salt to the wet mixture. Fold the mixture gently until just combined, being careful not to overmix to keep the bars tender.
- Incorporate M&M’s and Chocolate Chips: Stir in the Christmas M&M’s into the dough. Reserve 1 cup of this dough separately. To the remaining dough, fold in the semi-sweet chocolate chips.
- Layer the Dough in the Pan: Press the dough with chocolate chips evenly into the prepared baking pan. Then, take the reserved dough and press it gently over the top to mostly cover the bottom layer. Add extra M&M’s on top if desired for extra color and crunch.
- Bake the Cookie Bars: Place the pan in the oven and bake for 18-22 minutes, until the edges are golden brown, but the center remains slightly doughy for a soft chew.
- Add Chocolate Kisses and Melt: Remove the pan from the oven and immediately arrange the halved Hershey’s Milk Chocolate Kisses across the top. Return to the oven for 1-2 minutes to gently melt the chocolate.
- Finish and Serve: Sprinkle flaky sea salt over the warm cookie bars for a perfect sweet-and-salty finish. Serve warm or allow to cool completely. Store leftovers in an airtight container for up to 5 days.
Notes
- Do not overbake the cookie bars; they should be golden but still slightly soft in the center for the best texture.
- Chilling the browned butter briefly helps to prevent cooking the eggs in the batter when mixing.
- For extra festive flair, add more Christmas M&M’s on top before baking.
- Flaky sea salt enhances the flavor by balancing the sweetness with a salty crunch.
- These bars can be stored in an airtight container at room temperature for up to 5 days.
Nutrition
- Serving Size: 1 bar
- Calories: 210
- Sugar: 18g
- Sodium: 110mg
- Fat: 11g
- Saturated Fat: 6g
- Unsaturated Fat: 4g
- Trans Fat: 0.2g
- Carbohydrates: 27g
- Fiber: 1g
- Protein: 2g
- Cholesterol: 35mg
