One evening last spring, I found myself knee-deep in chocolate chips and peanut butter jars, determined to whip up something extra-special for my daughter’s school bake sale. You know the drill: rain pattering on the windowsill, kids arguing over TV shows in the next room, and me craving something warm, gooey, and utterly comforting. That’s when the idea hit—why not marry my favorite fudgy brownies with the classic peanut butter cookie bar? It sounded wild, but hey, life’s too short for boring desserts.
Fast-forward a frantic hour later, and I had these dreamy Peanut Butter Brookies cooling on the counter. The fudgy chocolate layer met the swirled peanut butter dough in a glorious mash-up, and everyone—from cranky teenagers to the sternest teachers—couldn’t stop raving. Trust me, once you bite into that chewy, buttery goodness, you’ll be completely hooked.
Why You’ll Love These Peanut Butter Brookies
- Ready in under an hour—even if your kitchen looks like a tornado just passed through.
- Double whammy of chocolate and peanut butter for maximum comfort-food satisfaction.
- Chewy brownie meets tender cookie bar in one sublime square (yes, really!).
- A little protein boost courtesy of creamy peanut butter—snack guilt-free-ish.
- Perfect for lunchboxes, potlucks, holiday gift boxes, or that much-needed movie-night pick-me-up.
- Hands-on swirl action—no piping bag required, so it feels extra fun (and a tiny bit artistic).
- Customizable for gluten-free, vegan, or just plain adventurous bakers with simple swaps.
- They keep well in an airtight container—bake on Sunday, snack all week (if they last that long!).
Ingredient Notes (with Tips & Substitutions)
Here’s the lowdown on what you’ll need and how to tweak it if your pantry is playing hard to get:
- Unsalted butter: We’re talking real butter here—no margarine, please! If you want dairy-free, swap in your favorite vegan butter stick.
- Semisweet chocolate chips: Ghirardelli or any quality brand you trust. Dark chocolate lovers can bump up the cocoa percentage for a richer zing.
- Granulated & light brown sugar: The combo gives you a shiny brownie top and chewy texture. You can try coconut sugar or honey for a different spin, though texture may shift.
- All-purpose flour: Straight up, spooned and leveled. For gluten-free, a 1:1 flour blend works like a charm.
- Unsweetened cocoa powder: If you’ve got Dutch-processed, use it. If not, regular natural cocoa is totally fine—just stir well to avoid lumps.
- Creamy peanut butter: No-stir natural is my fave for that pure, nutty flavor. Crunchy is cool too if you crave extra texture.
- Eggs & vanilla extract: Room temperature always helps everything come together smoothly. Don’t skip the vanilla—it’s like magic.
- Baking powder & sea salt: Just little pinch magic—keeps everything balanced and ever so slightly puffed.
Step-by-Step Directions
Ready to dive in? Grab your mixing bowls, parchment paper, and a spatula—you’re about to create something epic.
- Preheat & Prep: Heat your oven to 350°F (175°C). Line an 8×8-inch square pan with parchment paper, leaving a little overhang on two sides so you can pull your brookies out like a pro later on. Pro tip: Give the pan a quick spritz of nonstick cooking spray under the parchment so it doesn’t shimmy around.
- Melt Chocolate & Butter: Toss ½ cup cubed butter and 4 oz semisweet chips into a microwave-safe bowl. Zap in 20-second bursts, stirring in between, until everything’s glossy and smooth (should take about 3–4 bursts). No microwave? No sweat—set up a double boiler and melt gently over simmering water.
- Whisk in Sugars & Eggs: Stir in ¾ cup granulated sugar and 2 tablespoons packed brown sugar. Whisk like you mean it until the mix shines a bit. Then, one at a time, beat in 2 large eggs and 1 teaspoon vanilla, scraping the bowl so no drippy edges get left behind.
- Fold in Dry Ingredients: Sift (or whisk) together ¼ cup flour, 2 tablespoons cocoa powder, and ¼ teaspoon salt. Gently fold this into your wet batter—stop as soon as you don’t see streaks. Overmixing is the enemy of fudginess.
- Spread the Brownie Layer: Dump that glossy batter into your prepared pan. Smooth the top with an offset spatula or the back of a spoon so it’s about ½-inch thick. It won’t cover the whole pan yet—trust the process.
- Make the Peanut Butter Dough: In a separate bowl, beat ½ cup creamy peanut butter with ¼ cup softened butter until light and fluffy. Add ⅓ cup sugar and ⅓ cup brown sugar, then one egg and 1 teaspoon vanilla. Finally, stir in ¾ cup flour, ¼ teaspoon baking powder, and a pinch of salt until just combined.
- Dollop & Swirl: Drop spoonfuls of your peanut butter cookie dough over the brownie batter—no need to be neat. Grab a butter knife or skewer and swirl the two batters into a marbled masterpiece. (This is where you get to feel fancy!)
- Bake & Cool: Pop the pan in the oven for 25–28 minutes. You’re aiming for a toothpick that comes out with moist crumbs, not totally clean. Resist the urge to overbake—gooey is good! Let the brookies cool for at least 30 minutes on a wire rack, then use the parchment overhang to lift them out. Slice into 16 squares (or bigger, if you’re feeling indulgent).
Variations & Flavor Twists
Because we all need options, right?
- Swap the creamy peanut butter for almond or cashew butter to mix things up.
- Stir in ¼ cup mini chocolate chips or chopped nuts for extra pockets of surprise.
- Sprinkle flaky sea salt or a dusting of cinnamon sugar on top before baking for a little extra drama.
- Add a teaspoon of instant espresso powder to the brownie batter for a mocha kick.
- Make mini “brookie bombs” by using a mini-muffin tin—party bites for the win!
- Go vegan by swapping eggs for flax eggs and using dairy-free chocolate chips.
Storage & Reheating Tips
Believe me, these brookies will disappear fast, but if you manage to stash a few away:
- Room Temperature: Store in an airtight container for up to 3 days. (Good luck!)
- Refrigerator: Keeps for up to 7 days—just let them sit at room temp for 15 minutes before diving in.
- Freezer: Flash-freeze in a single layer on a sheet pan, then tuck into a freezer bag for up to 1 month. Thaw on the counter or microwave for 10–15 seconds when you need a warm treat.
Final Thoughts
There you have it—my go-to comfort-food mash-up that’s part brownie, part peanut butter cookie, and all kinds of cozy. These Peanut Butter Brookies are equal parts fuss-free and totally show-stopping, perfect for when you want to impress without spending all afternoon in a hot kitchen. Give ’em a whirl, and don’t forget to let me know how yours turn out (or if you sneak an extra square before they cool!). Drop a comment below or tag me on Instagram—I’m always here to cheer on your kitchen adventures.
Happy baking, friends! Remember: life’s short, eat more brookies.
Peanut Butter Brookies
Ingredients
- 1/2 cup unsalted butter cut into cubes
- 4 oz semisweet chocolate chips (Ghirardelli recommended)
- 3/4 cup granulated sugar
- 2 tablespoons light brown sugar packed
- 2 large eggs room temperature
- 1 tsp vanilla extract
- 1/4 cup all-purpose flour spooned and leveled
- 2 tablespoons unsweetened cocoa powder (Dutch-processed if available)
- 1/4 tsp fine sea salt
- 1/2 cup creamy peanut butter (no-stir natural variety recommended)
- 1/4 cup unsalted butter softened
- 1/3 cup granulated sugar
- 1/3 cup light brown sugar packed
- 1 large egg room temperature
- 1 tsp vanilla extract
- 3/4 cup all-purpose flour
- 1/4 tsp baking powder
- pinch fine sea salt
Instructions
- Preheat oven to 350°F (175°C). Line an 8x8-inch square pan with parchment paper, leaving overhang. Lightly spray with nonstick cooking oil.
- Combine butter and chocolate chips in a microwave-safe bowl. Microwave in bursts until smooth. Alternatively, use a double boiler to melt.
- Add sugars to the melted mix, whisk until glossy. Beat in eggs and vanilla. Fold in dry ingredients.
- Pour brownie batter into prepared pan, smoothing the top.
- Beat peanut butter and softened butter. Add sugars, then egg and vanilla. Stir in flour, baking powder, and salt.
- Drop spoonfuls of peanut butter dough over brownie layer. Use a knife to swirl the batters into a marbled pattern.
- Bake for 25-28 minutes. Let cool for 30 minutes before slicing into squares.
