These Dark Chocolate Peanut Butter Cup Blondies are gluten-free, reduced in sugar, and incredibly satisfying. They bake in just 20 minutes and are easy to prepare — rich, buttery blondie bars layered with creamy peanut butter and a glossy dark chocolate topping.
Think of a homemade candy bar: a chewy, buttery blondie base studded with dark chocolate, a thick layer of real peanut butter, and a final dark chocolate coat. Once you try these, packaged candy bars will feel unnecessary.
These bars are dangerously addictive. I’ve found myself slicing one large square “just for a taste” and inevitably going back for more. The combination of oat-flour blondies, real peanut butter, and high-quality dark chocolate creates a dessert that’s both nostalgic and elevated.
Why these blondies beat store-bought candy
Homemade ingredients make the difference. Use a good dark chocolate — chips, chunks, or a high-cocoa chocolate bar melted down — for a deep, fudgy chocolate finish. For the peanut butter layer, natural peanut butter (ingredients: peanuts, maybe salt) gives a true nutty flavor without extra oils and sugar. It creates that authentic peanut butter cup taste.
The blondie base is what makes these bars special: a chewy, buttery layer made from oat flour, brown sugar, melted butter, and a touch of baking powder and salt. Adding dark chocolate chunks into the blondie batter gives texture and pockets of melty richness.
Tips for the best results
- Use high-quality dark chocolate with cocoa or chocolate listed before sugar for the best flavor.
- When melting chocolate, go slowly. Microwave in 20–30 second bursts, stirring between intervals, to avoid burning the chocolate.
- If natural peanut butter is very thick, warm it briefly to make spreading easier — either by placing the jar in warm water or heating it in the oven for a couple minutes before spreading.
Ingredients
Blondie Bars:
- 6 tablespoons salted butter, melted
- ¼ cup natural peanut butter
- ½ cup packed brown sugar
- 1 cup oat flour (blend rolled oats to make your own)
- ¾ teaspoon baking powder
- ¼ teaspoon salt
- 1 egg
- 1 teaspoon vanilla extract
- ½ cup dark chocolate chunks (fold into batter)
Topping:
- ¾ cup natural peanut butter (for the peanut butter layer)
- 1 cup dark chocolate chunks, melted with coconut oil for smoothing
- 1–2 teaspoons coconut oil (optional, helps melt and spread chocolate)
- Optional: chopped peanuts or flaky sea salt for garnish
Substitutions and variations
- Less sugar: You can try coconut sugar or maple syrup in place of brown sugar; this recipe hasn’t been fully tested with swaps, so results may vary.
- Different nut butter: Regular peanut butter works, and almond or cashew butter will be delicious too. For a nut-free option, use sunflower seed butter.
- Vegan: Replace the egg with a flax egg and use dairy-free chocolate to make these bars vegan-friendly.
Instructions
- Preheat oven to 350°F and line an 8×8 baking dish with parchment paper.
- Melt the butter, then stir in ¼ cup peanut butter until combined.
- In a bowl, whisk together oat flour, brown sugar, baking powder, and salt.
- Pour the butter and peanut butter mixture into the dry ingredients, then add the egg and vanilla. Mix until a sticky dough forms.
- Fold in ½ cup dark chocolate chunks. Press the batter into the prepared baking dish and bake at 350°F for 18–20 minutes, until edges are lightly golden and a toothpick comes out clean.
- While the bars are still warm, spoon the remaining ¾ cup peanut butter on top. Let it warm slightly, then gently spread into an even layer.
- Melt 1 cup chocolate chunks with 1–2 teaspoons coconut oil in 20–30 second microwave intervals, stirring frequently. Alternatively, melt over a double boiler.
- Pour the melted chocolate over the peanut butter layer. Tilt the dish to help the chocolate spread evenly without blending into the peanut butter.
- Optionally sprinkle chopped peanuts or flaky sea salt onto the melted chocolate.
- Chill in the fridge or freezer for at least an hour until the chocolate sets. Remove the parchment and transfer to a cutting board. Use a sharp knife to slice into nine bars. Store in the refrigerator for up to a week.
Notes
If your natural peanut butter is too thick to spread, place the pan back in the warm oven for a couple minutes to soften the peanut butter before spreading.
These blondies offer a simple way to make an elevated, homemade version of a peanut butter cup — chewy, nutty, and rich with dark chocolate. If you try the recipe, enjoy and feel free to adapt it to your dietary preferences.
Recipe details
- Author: Marley Braunlich
- Prep Time: 10 minutes
- Cook Time: 20 minutes
- Total Time: 30 minutes
- Yield: 9 bars