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Peanut Butter Blondies

By: Author Jenna Margot

Posted on

Peanut Butter Blondies

Peanut Butter Blondies Recipe

Hey y'all! If you love rich peanut butter flavor, fudgy centers, and crinkly, caramelized edges, these Peanut Butter Blondies are your new go-to treat. They whip up in one bowl, bake fast, and wow at bake sales, potlucks, or cozy weeknights. Let's get cooking!

  • Yield: 16 squares
  • Prep Time: 10 minutes
  • Cook Time: 25 minutes
  • Cooling Time: 30 minutes
  • Total Time: 1 hour 5 minutes
  • Oven Temp: 350°F (175°C)
  • Pan: 8-inch square metal pan

Why You'll Love These Peanut Butter Blondies

  • One-bowl batter means minimal dishes and maximum flavor.
  • Chewy, gooey texture with golden, crisp edges every time.
  • Perfect balance of sweet brown sugar and salty peanut butter.
  • Easy to customize with chocolate chips, peanuts, or swirls.
  • Bake in 25 minutes and slice into neat, crowd-pleasing bars.

Ingredients

  • ½ cup (113 g) unsalted butter, melted and slightly cooled
  • 1 cup (200 g) packed light brown sugar
  • ½ cup (130 g) creamy peanut butter, room temperature
  • 1 large egg plus 1 large egg yolk, room temperature
  • 1 ½ teaspoon pure vanilla extract
  • 1 cup (120 g) all-purpose flour
  • ½ teaspoon baking powder
  • ¼ teaspoon baking soda
  • ½ teaspoon fine sea salt
  • ½ cup (85 g) semisweet chocolate chips or chunks, optional
  • ⅓ cup (45 g) chopped roasted peanuts, optional
  • 2 tablespoon creamy peanut butter, melted, for swirl on top, optional

How to Make Peanut Butter Blondies

Step 1: Prep the pan and oven

Heat oven to 350°F (175°C). Line an 8-inch square metal pan with parchment, leaving overhang on two sides for a sling. Lightly mist with nonstick spray.

Step 2: Whisk the wet ingredients

In a medium bowl, whisk melted butter, brown sugar, and peanut butter until glossy and smooth, about 30 seconds. Whisk in the egg, egg yolk, and vanilla until fully combined and slightly thickened, 30 to 45 seconds.

Step 3: Add the dry for the blondie batter

Sprinkle flour, baking powder, baking soda, and salt over the bowl. Switch to a spatula and fold just until no dry streaks remain. Do not overmix.

Step 4: Fold-ins and pan it

Fold in chocolate chips and peanuts if using. Scrape the batter into the prepared pan and smooth the top. If swirling, dollop melted peanut butter in 5 to 6 small spots and drag a knife gently to create swirls.

Step 5: Bake the blondies

Bake for 25 minutes, until the edges are set and deep golden and the center looks slightly shiny and puffed. A toothpick should emerge with a few moist crumbs. Start checking at 22 minutes.

Peanut Butter Blondies

Step 6: Cool and slice

Cool in the pan on a rack for 30 minutes. Use the parchment sling to lift out and cut into 16 squares. For extra neat edges, chill 15 minutes before slicing.

Notes for Better Blondies

  • Measure flour accurately to avoid cakey bars; spoon and level or, better yet, weigh it. Helpful guide: how to measure flour.
  • Room temp ingredients mix more evenly and create a smoother, glossier batter.
  • Curious about nutrition benefits of peanuts and peanut butter? Check out this overview from Harvard T.H. Chan: peanuts and peanut butter.

Variations: Fun Twists on Blondie Bars

  • Peanut Butter Cup Chunky: Fold in 1 cup chopped mini peanut butter cups and drizzle with melted chocolate after baking.
  • Salted Pretzel Crunch: Swap peanuts for ½ cup crushed pretzels and finish with a pinch of flaky sea salt.
  • Double Chocolate Peanut: Use ¼ cup natural cocoa in place of ¼ cup flour and add ¾ cup chocolate chips.

Equipment

  • 8-inch square metal baking pan
  • Parchment paper and nonstick spray
  • Mixing bowl and whisk
  • Rubber spatula
  • Measuring cups/spoons or digital kitchen scale
  • Offset spatula or butter knife for swirling

Storage & Make-Ahead

Room temperature: Store sliced bars in an airtight container for up to 3 days. For best texture, keep at cool room temp and stack with parchment between layers.

Refrigerator: Up to 5 days; let sit 15 minutes before serving for the fudgy texture to return.

Freezer: Wrap individual bars tightly and freeze up to 2 months. Thaw at room temp 30 to 60 minutes or warm 10 to 15 seconds in the microwave.

Serving Ideas & Pairings for Peanut Butter Blondies

  • Serve warm with a scoop of vanilla ice cream and a drizzle of warm peanut butter or chocolate sauce.
  • Pair with hot coffee, cold milk, or a salted caramel latte for a sweet-salty combo.
  • Crumble over yogurt or ice cream parfaits for a quick dessert.

Pro Tips for Peanut Butter Blondies

  • Use visual cues: edges should be set and golden while the center remains slightly soft; a few moist crumbs on a tester are perfect. More details here: doneness cues.
  • Weigh ingredients for precision, especially flour and peanut butter, to keep the crumb fudgy, not cakey.
  • Underbake by 1 to 2 minutes if you prefer extra gooey centers; carryover heat will finish the bake.

FAQ: Peanut Butter Blondies

Can I use natural peanut butter? Yes, but use a well-stirred, no-stir style for best results. If your peanut butter is very runny, add 1 to 2 tablespoon extra flour to maintain structure.

Can I double the recipe? Absolutely. Bake in a 9x13-inch pan at 350°F (175°C) for about 26 to 30 minutes, checking at 25. Cool before slicing.

How do I make them gluten-free? Substitute a quality 1:1 gluten-free all-purpose blend by weight (120 g) and let the batter rest 10 minutes before baking to hydrate.