Equipment
Ingredients
Chocolate Fudgy Base
- 115 g unsalted butter, melted and warm
- 250 g granulated sugar
- 80 g dutch-process cocoa powder
- 2 g salt
- 5 ml vanilla extract
- 2 eggs, cold
- 70 g all-purpose flour
Peanut Butter Swirl
- 130 g creamy peanut butter
- 30 g powdered sugar
- 15 g unsalted butter, melted
- 2 g flaky sea salt
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 212 kcal
- Protein
- 4 g
- Carbohydrates
- 26 g
- Fat
- 12 g
- Fiber
- 2 g
- Sugar
- 18 g
- Sodium
- 110 mg
- Saturated Fat
- 6 g
- Trans Fat
- 0 g
- Monounsaturated Fat
- 4 g
- Polyunsaturated Fat
- 1 g
- Cholesterol
- 41 mg
- Potassium
- 137 mg
- Calcium
- 17 mg
- Iron
- 1.0 mg
- Magnesium
- 41 mg
- Phosphorus
- 83 mg
- Zinc
- 0.7 mg
- Vitamin A
- 66 mcg
- Vitamin D
- 0.1 mcg
- Vitamin E
- 1.0 mg
- Vitamin K
- 1 mcg
- Vitamin B6
- 0.1 mg
- Vitamin B12
- 0.1 mcg
- Thiamin
- 0.02 mg
- Riboflavin
- 0.06 mg
- Niacin
- 1.2 mg
- Folate
- 13 mcg
- Water
- 7 g
- Alcohol
- 0 g
- Caffeine
- 12 mg
Sources: USDA FoodData Central
Method
Preheat the oven to 165°C/325°F. Line a 20cm (8-inch) square baking pan with parchment paper, leaving an overhang on two sides for easy removal.
In a small bowl, combine the peanut butter, powdered sugar, and the small amount of melted butter (15g). Stir vigorously until smooth and slightly stiffened. Set aside.
In a large heatproof bowl, combine the warm melted butter (115g), granulated sugar, cocoa powder, and fine salt. Whisk vigorously for 1 minute until the mixture looks gritty but cohesive.
Add the vanilla extract and cold eggs one at a time, whisking hard after each addition until the batter becomes shiny, thick, and pulls away from the sides of the bowl.
Switch to a spatula. Add the flour and fold gently just until no streaks of white remain. Do not overmix.
Pour the chocolate batter into the prepared pan and smooth the top. Drop teaspoon-sized dollops of the peanut butter mixture over the surface. Use a knife or skewer to swirl the peanut butter into the chocolate, creating a marbled effect.
Bake for 30-35 minutes. A toothpick inserted into the center should come out with moist crumbs attached, not wet batter. Do not overbake, or they will lose their fudgy texture.
Sprinkle flaky sea salt over the hot bars immediately upon removing from the oven. Let cool completely in the pan on a wire rack for at least 2 hours before slicing.
Chef's Notes
- Using cold eggs is a specific technique here; it shocks the warm butter, helping to create that dense, fudgy core rather than a fluffy cake crumb.
- Dutch-process cocoa is non-negotiable for the 'Midnight' look and flavor; natural cocoa is too acidic and will change the texture.
- These bars are actually better on day two, making them the perfect make-ahead treat for events.
- If you want a cleaner cut, chill the fully cooled pan in the fridge for 30 minutes before slicing.
Storage
Refrigerator: 1 week — Texture becomes denser and more fudge-like when chilled.
Freezer: 3 months — Wrap individually in foil before freezing.
Reheating: Microwave for 10-15 seconds to restore gooey texture.
Troubleshooting
Bars are dry or cakey
Cause: Overbaking or overmixing the flour
Fix: Serve warm with ice cream or milk to mask dryness
Prevention: Remove from oven when crumbs are still moist; stop mixing immediately after flour disappears
Peanut butter swirl sunk to the bottom
Cause: Peanut butter mixture was too heavy/dense compared to batter
Fix: Cannot be fixed, but still tastes delicious
Prevention: Ensure the powdered sugar is mixed in well to stiffen the peanut butter slightly
Cultural Context
While brownies are a quintessential American invention from the late 19th century, the combination of chocolate and peanut butter gained massive popularity in the mid-20th century, particularly in the Midwest (home of the Buckeye candy). This recipe deconstructs the Buckeye concept into a tray-bake format.
