Name: Peanut Butter Swirl Brownies
Prep time: 10 min
Cook time: 25 min
Total time: 35 min
Cuisine: American
Ingredients: 1/2 cup peanut butter; 1/4 cup oil (or melted butter); 1/4 cup milk of choice; 1 tbsp pure vanilla extract; 1 cup sugar (unrefined if desired); 1/2 cup unsweetened cocoa powder; 1/2 cup all-purpose flour or oat flour; 1/4 tsp salt; 1/4 tsp baking powder; Optional: 1/2 cup chocolate chips

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Fudgy, decadent, and swirled with creamy peanut butter, these Peanut Butter Swirl Brownies are a nostalgic twist on a classic treat. The rich cocoa flavor mingles beautifully with ribbons of peanut butter, creating a dessert that's both comforting and indulgent. Whether I make them for a casual afternoon snack or a festive holiday spread, these brownies never last long.

Peanut Butter Swirl Brownies

Ingredients

(Tip: You'll find the full list of ingredients and measurements in the recipe card below.)

½ cup peanut butter

¼ cup oil (or melted butter)

¼ cup milk of choice

1 tablespoon pure vanilla extract

1 cup sugar (unrefined if desired)

½ cup unsweetened cocoa powder

½ cup all-purpose flour or oat flour

¼ teaspoon salt

¼ teaspoon baking powder

Optional: ½ cup chocolate chips

Directions

I start by preheating the oven to 325°F (160°C) and lining an 8×8-inch baking pan with parchment paper.

In a large bowl, I mix together the peanut butter, oil, milk, vanilla, and sugar until everything is smooth.

Then I add the cocoa powder, flour, salt, and baking powder, stirring until fully combined.

If I'm using chocolate chips, I gently fold them into the batter.

I pour the batter into the prepared pan and smooth it out evenly.

I warm a few tablespoons of peanut butter and drizzle it over the top, then use a knife or toothpick to swirl it into the batter for that signature marbled look.

I bake for 25 minutes, removing the brownies when the center is just set and a toothpick comes out mostly clean for that perfectly fudgy texture.

I let them cool completely in the pan before slicing, as they firm up beautifully as they cool.

Servings and timing

This recipe makes 12 brownies.

Prep Time: 10 minutes

Cook Time: 25 minutes

Total Time: 35 minutes

Calories per serving: 190 kcal

Variations

I like swapping in almond butter or cashew butter for a different flavor profile. For a richer brownie, I sometimes use melted butter instead of oil. If I want more texture, I’ll sprinkle chopped nuts or mini chocolate chips on top before baking. For a fully gluten-free version, oat flour works just as well as all-purpose. I’ve even tried adding a dash of espresso powder to enhance the chocolate flavor—it’s amazing.

Storage/Reheating

I store the brownies in an airtight container at room temperature for up to 3 days or refrigerate them for up to a week. To freeze, I wrap them individually and place in a freezer-safe bag—they keep well for up to 2 months. I reheat them in the microwave for about 10-15 seconds to get that fresh-out-of-the-oven warmth.

FAQs

How do I get the perfect swirl on top?

I warm a few tablespoons of peanut butter to make it more pourable, then drizzle it over the brownie batter and gently swirl with a knife or toothpick for that marbled effect.

Can I make these brownies gluten-free?

Yes, I use oat flour as a great gluten-free alternative to all-purpose flour in this recipe, and it still produces a chewy, fudgy texture.

What kind of peanut butter works best?

I like using a creamy, natural peanut butter without added sugar or oils. It swirls better and gives a more authentic peanut flavor.

Can I reduce the sugar in the recipe?

While I haven’t tried drastically reducing it, I sometimes use unrefined sugars like coconut sugar, which adds a deeper flavor without sacrificing texture.

Why do the brownies need to cool completely before slicing?

Letting them cool helps the brownies firm up and develop that dense, fudgy texture. If I cut them too soon, they tend to fall apart.

Conclusion

These peanut butter swirl brownies are everything I love in a dessert: rich, satisfying, and surprisingly easy to make. Whether I’m baking for a party, a family treat, or just to satisfy my chocolate cravings, this recipe always hits the spot. With minimal effort and maximum flavor, it’s a sweet twist on tradition I keep coming back to.

Recipe:

Peanut Butter Swirl Brownies

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Author: Cheryl
Total Time: 35 minutes
Yield: 12 brownies
Diet: Vegetarian

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Description

Fudgy and indulgent brownies swirled with creamy peanut butter for a rich, chocolatey treat that's easy to make and naturally dairy-free. Perfect for any occasion, from casual snacks to festive gatherings.

Instructions

Preheat the oven to 325°F (160°C) and line an 8×8-inch baking pan with parchment paper.
In a large bowl, mix together the peanut butter, oil, milk, vanilla, and sugar until smooth.
Add the cocoa powder, flour, salt, and baking powder, stirring until fully combined.
Fold in chocolate chips, if using.
Pour the batter into the prepared pan and smooth it out evenly.
Warm a few tablespoons of peanut butter and drizzle over the top. Use a knife or toothpick to swirl it into the batter.
Bake for 25 minutes, or until the center is just set and a toothpick comes out mostly clean.
Let the brownies cool completely in the pan before slicing and serving.