Red, White, & Blue M&M Cookie Bars
Servings
24
Prep Time
15 minutes
Bake Time
24 minutes
These Patriotic M&M Cookie Bars are soft, chewy, and and full of rich, caramelized brown butter flavor. Filled with festive red, white, and blue M&Ms and melty chocolate, they’re perfect for 4th of July, Memorial Day, Labor Day, and any Patriotic celebration. We hope you have as much fun making them as we do!
Ingredients
-
255 g (2 sticks + 2 Tbsp / 1¼ cups) unsalted butter (will reduce to about 208 g after browning)
- 360 g (3 cups) all-purpose flour
-
5 g (1 tsp) baking soda
-
4 g (1½ tsp) cornstarch
- ¾ tsp salt
-
200 g (1 cup) light or dark brown sugar, packed
- 100 g (½ cup) granulated sugar
- 2 eggs, room temperature
- 1 egg yolk, room temperature
- 13 g (1 Tbsp) vanilla extract
-
30 ml (2 Tbsp) whole milk, room temperature
-
250 g (about 1¼ cups) red, white, and blue M&Ms
- 120 g (⅔ cup) semisweet chocolate chips
-
100 g (about ½ cup) red, white, and blue M&Ms
-
24 g (2 Tbsp) patriotic sprinkles (jimmies, stars, etc.)
- 45 g (¼ cup) semisweet chocolate chips
Cookie Bars
Topping (optional)
Instructions
Brown Butter
In a light-colored pan over medium heat, stir the butter constantly with a rubber spatula until it foams, turns golden brown, and develops a nutty aroma (6–10 minutes). Brown milk solids will form at the bottom.
Immediately pour the browned butter with the milk solids into a heatproof measuring glass. You should have about 204–210 g (just under 1 cup). If too much liquid evaporates, add 1–3 teaspoons of water to reach the correct amount.
Let the butter cool to room temperature (74–90°F) before using, about 40–45 minutes on the counter or 20–25 minutes in the fridge. It should still be pourable.
Cookie Bars
Preheat oven to 350°F and position rack in the center.
Line a 9×13" metal baking pan with parchment paper, leaving an overhang for easy removal.
In a medium bowl, whisk together flour, baking soda, cornstarch, and salt. Set aside.
In a large bowl, whisk the cooled brown butter, brown sugar, and granulated sugar until smooth and glossy, 1–2 minutes.
Add eggs, egg yolk, milk, and vanilla. Whisk until light and creamy, about 1 minute.
Add the dry ingredients in two additions, folding with a spatula just until only a few flour streaks remain.
Fold in the M&Ms and chocolate chips until evenly combined and no flour streaks remain. Do not overmix.
Press dough evenly into the prepared pan. Top with extra M&Ms, chocolate chips, and patriotic sprinkles.
Bake for 22–26 minutes, checking at 20. The edges should be golden and the center set with no longer shiny. A toothpick inserted in the center should come out with a few moist crumbs. If unsure, underbake slightly for a chewier texture (the bars will continue setting as they cool). Rotate pan halfway through baking, and tent with foil if browning too quickly.
Let the bars cool in the pan on a wire rack for 40 minutes, then lift them out using the parchment and let cool completely on the rack, about 1 hour.
Slice the bars into squares with a sharp knife, wiping the blade clean between cuts. Serve at room temperature.
Did you make this? We’d love to hear how it turned out! Leave a review
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Notes
- Servings: Makes 12–24 bars (cut into 3×4 large or 4×6 regular squares).
- Storage: Unfrosted bars keep for 3 days at room temp or 1 week in the fridge. Frosted bars can sit out for 1 day, but are best refrigerated for up to 5 days. Freeze baked bars in an airtight container for up to 6 months.
- Before Starting: Measure and prep all ingredients in advance to keep things smooth as you go. We can’t recommend a food scale enough—it's faster and more accurate.
- Mixing: You can use a hand mixer instead of a whisk, or a stand mixer fitted with the paddle attachment on low. Just be mindful—cookie bar batter is thicker and easier to overmix in a stand mixer. Whichever method you choose, mix until just combined to avoid a cakey texture.
- Brown Butter: Browning butter evaporates some of the liquid, so always measure the final amount. Add water as needed to reach the correct quantity.
- Chocolate Chips: Can use any combination of bittersweet, semisweet, or dark chocolate.
- Decorating: For a more aesthetic look, place the decorative M&Ms on top with the 'M' face down. (Yes, it’s extra, but you know that’s how we roll at Birchberry)
- Baking Sheet: A light-colored metal pan bakes more evenly than glass or dark metal.
- Oven Temperature: A consistent oven temp is key to a level top and gooey center. If your oven runs hot, tent with foil earlier and reduce baking time slightly. We recommend using an oven thermometer to track the temperature.
- Doneness: Be careful not to overbake, or the bars can turn dry and crumbly. If in doubt, slightly underbake for a chewier texture. Be sure to rotate the pan about 10-12 minutes into baking.
- Sinkage: It’s normal for the center to sink slightly as it cools—this happens when the edges set before the middle, especially with thick, chewy bars. If the bars sink more deeply or unevenly, they may have been slightly underbaked, overmixed (after adding the eggs or dry ingredients), or the oven may have been hotter than the setting, causing the edges to bake faster than the center. The texture inside may turn out more fudgy, sweet, and rich—but still delicious!
Happy baking! ❤️
Emma & Eric
@birchberryco Easy 4th of July dessert! 🇺🇸 For full recipe click on RECIPES then Red, White & Blue M&M'S Cookie Bars on our site Birchberryco.com (link in bio) #4thofjuly #independenceday #fourthofjuly #4thofjulyparty #cookies #chocolatechipcookies #baking #bakingrecipe #baketok #aesthetic #asmr #cottagecore
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