Go Back
Fudgy Peanut Butter Brownies

Fudgy Peanut Butter Brownies

Fudgy Peanut Butter Brownies are rich, chewy chocolate treats swirled with creamy peanut butter for the perfect balance of sweet and salty indulgence. Easy to bake and endlessly customizable, they’re a decadent dessert that’s loved by all ages.
Prep Time 15 minutes
Cook Time 30 minutes
Total Time 45 minutes
Servings 9

Ingredients
  

For the brownie base:

  • ¾ cup 4.5 oz semi-sweet chocolate, coarsely chopped
  • ¾ cup unsalted butter
  • ¾ cup granulated sugar
  • ¾ cup dark brown sugar
  • 3 eggs at room temperature
  • 2 teaspoons vanilla extract
  • A few drops of almond extract
  • 1 cup all-purpose flour
  • tablespoons unsweetened cocoa powder

For the peanut butter swirl:

  • cup peanut butter
  • 5 tablespoons powdered sugar
  • ½ teaspoon vanilla extract optional
  • 2 to 3 tablespoons cream double, whipping, or heavy cream

Instructions
 

For the brownie base:

  • Preheat the oven to 350ºF (180ºC).
  • Grease or spray an 8-inch square metal baking pan (avoid using glass), and line the bottom and two sides with parchment paper, leaving the remaining two sides unlined for easy lifting.
  • In a large microwave-safe bowl, melt the chocolate and butter together, stirring every 10 seconds until the mixture is smooth. Alternatively, melt them over a pot of simmering water, making sure the bottom of the bowl doesn’t touch the water, and stir until fully melted.
  • Stir in the granulated and brown sugars until well blended.
  • Add the eggs, vanilla extract, almond extract (if using), and cocoa powder. Mix until fully combined.
  • Gradually add the flour in two additions, mixing gently each time—avoid overmixing.
  • Pour and spread the brownie batter evenly into the prepared pan.

For the peanut butter swirl:

  • In a medium bowl, combine the peanut butter, powdered sugar, vanilla (if using), and cream. Stir until the mixture is smooth and no lumps remain.
  • Drop spoonfuls of the peanut butter mixture over the brownie batter. Use a knife to gently swirl it into the batter, making sure to leave some large streaks or chunks intact to maintain the marbled effect.
  • Bake for 25 to 30 minutes, depending on your pan, until the top looks dry, the center is slightly jiggly, and a toothpick or cake tester inserted comes out with moist, fudgy crumbs. Do not overbake.
  • Let the brownies cool completely on a wire rack.
  • They taste even better the next day—wrap them in plastic and store at room temperature.

For longer storage, wrap them well and freeze.

    Notes

    Avoid using a glass pan, as the brownies won’t set properly in the center—always use a metal pan for best results.
    For the peanut butter, I usually go with traditional commercial peanut butter, but natural peanut butter works just as well.
    When creating the swirl, be gentle. You want the peanut butter mixture to remain distinct from the brownie batter, so don’t over-swirl—this helps maintain those beautiful ribbons and rich flavor contrast.
    Pan size is key to achieving a perfectly fudgy, gooey texture that bakes evenly throughout.
    When lining your pan, I highly recommend using just a single strip of parchment paper cut to the width of the pan. This will line only the bottom and two opposite sides. Avoid lining the whole pan with a square of paper that folds in the corners—since the brownie is very fudgy, it may stick to those folds.
    When baking, aim to slightly underbake the brownies. The center should still have a jiggle when you take them out of the oven—this ensures that soft, gooey bite everyone loves.
    For the best flavor and texture, wait until the next day to eat them. Letting them sit allows the brownies to fully develop in taste and structure. These brownies also freeze very well when wrapped tightly and can last at least a month in the freezer.
    For an almond butter variation, substitute almond butter in the same amount as peanut butter. You can also replace the cocoa powder by grinding 2 tablespoons of cocoa nibs into a fine powder. For a different sweetness, try using coconut sugar instead of brown sugar. The rest of the recipe stays exactly the same.