This Buckeye Brownies recipe began as a serious indulgence I made for a family gathering when I wanted something that combined two all-time favorites: dense, fudgy chocolate and creamy peanut butter. I first discovered this flavor pairing while experimenting with layered bars one winter weekend; the result was so rich and nostalgic that everyone asked for the recipe. These bars have a glossy chocolate crust, a pillow-soft peanut butter center, and a dense brownie base that stays fudgy without being underbaked. The texture contrast — slightly crackly top, chewy middle, and velvety filling — is what keeps people coming back for a second piece.

I love making these for holidays and potlucks because they travel well and can be made ahead. The peanut butter layer softens into a spreadable, candy-like filling as the ganache chills, giving each bite that classic Buckeye candy vibe but in bar form. The method is forgiving: melt, stir, mix, and chill. Still, a few technique notes — like letting eggs come to room temperature and not overbaking the base — make a big difference in achieving that ideal gooey crumb. I often use a high-quality dark chocolate for the ganache to balance the sweetness and a reliable creamy peanut butter like Skippy for creaminess.

Ingredients

• Brownie Base: Use 1 cup (2 sticks) unsalted butter melted — good-quality butter (e.g., Land O'Lakes or Kerrygold) gives a rich mouthfeel. Combine with 2/3 cup unsweetened cocoa powder for deep chocolate flavor and 1 cup all-purpose flour to provide structure, while 2 cups granulated sugar lends sweetness and a glossy top.
• Eggs & Vanilla: Four large eggs at room temperature help create a fudgy crumb and glossy crust; 3 tablespoons pure vanilla extract adds aromatic warmth. Room-temperature eggs emulsify better and give lift without drying the brownie.
• Peanut Butter Filling: 1 1/2 cups creamy peanut butter (I used Skippy for its smooth sweetness) plus 3/4 cup unsalted butter melted and cooled create a stable, spreadable layer. Add 3 cups powdered sugar, sifted, to avoid lumps and ensure a silky texture.
• Ganache: One 10-ounce package dark chocolate chips and 1/3 cup heavy cream make a shiny, sliceable top. Choose 60–72% dark chocolate to balance sweetness from the filling and base.
• Salt: 1/2 teaspoon table salt in the base (or flaky sea salt on top) enhances all the flavors and prevents the final bars from tasting flat.

Instructions

Prepare the Pan & Oven: Preheat the oven to 350°F. Line a 9x13-inch baking pan with parchment paper leaving an overhang on two sides; this makes lifting the cooled slab out effortless. Position a rack in the center of the oven for even heat. Make the Chocolate Base: In a medium bowl whisk together 1 cup melted unsalted butter and 2/3 cup unsweetened cocoa powder until smooth. Add 1 cup all-purpose flour, 2 cups granulated sugar and 1/2 teaspoon salt and whisk until crumbly. Add 4 room-temperature large eggs and 3 tablespoons vanilla and beat briefly with a handheld mixer on low just until combined. Spread batter into the prepared pan and bake for 23–25 minutes — a toothpick should come out with a few moist crumbs. Mix the Peanut Butter Filling: While brownies bake, combine 3/4 cup melted unsalted butter with 1 1/2 cups creamy peanut butter and 2 teaspoons vanilla using a handheld mixer on medium-low until smooth. Reduce speed and add 3 cups sifted powdered sugar, one cup at a time, mixing until thick and creamy. The filling will be dense but spreadable when warm brownies are out of the oven. Prepare the Ganache: Place 10 oz dark chocolate chips in a heatproof bowl. Heat 1/3 cup heavy cream in the microwave for 50–60 seconds until it just begins to bubble. Pour hot cream over chips, wait 1–2 minutes, then stir gently until glossy and fully combined. If needed, microwave in 5-second bursts while stirring. Assemble the Layers: Immediately after removing the brownies from the oven, drop spoonfuls of the peanut butter filling across the hot surface. Use a spoon or offset spatula to gently spread an even layer, taking care not to press into the base. Pour the ganache over the peanut butter and use a spatula to spread into an even top. Chill & Slice: Refrigerate for about 2 hours or until the ganache is set. Use the parchment overhang to lift the chilled slab onto a cutting board and slice into 12 even pieces with a sharp knife. Wipe the knife clean between cuts for neat edges.

Storage Tips

Store chilled bars in an airtight container in the refrigerator for up to 5 days to preserve texture and prevent the ganache from becoming sticky at room temperature. If you need to store at room temperature for a short period, keep them on a cool tray away from direct sunlight and serve within a day. For long-term storage, freeze individually wrapped bars in plastic wrap and then in a resealable freezer bag for up to 3 months. To serve from frozen, thaw overnight in the refrigerator and bring to room temperature for 20–30 minutes so flavors bloom.

Ingredient Substitutions

For a nut-free version, replace the peanut butter with a sunbutter (sunflower seed butter) using the same ratio; the texture will be slightly less sweet and a touch earthier. To make the ganache milkier, swap dark chocolate chips for milk chocolate chips 1:1 — reduce cream by a tablespoon if you prefer a firmer top. For a gluten-free option, substitute the all-purpose flour with 1-to-1 gluten-free flour blend, but expect a slightly different crumb. Use natural peanut butter with added powdered sugar if you prefer a less sweet filling, adjusting powdered sugar to taste.

Serving Suggestions

Serve chilled or at cool room temperature. Garnish with a sprinkle of flaky sea salt on the ganache for contrast, or top each square with 1–2 roasted chopped peanuts for crunch. Pair a small square with a glass of cold milk or a robust cup of coffee to balance the richness. For dessert plates, add a scoop of vanilla ice cream and a drizzle of chocolate sauce to create an upscale presentation suitable for dinner parties.

Cultural Background

The Buckeye candy is a Midwestern American classic inspired by the Ohio buckeye nut; it’s typically a peanut-butter center dipped in chocolate. Transforming that iconic candy into a bar merges two American baking traditions: dense, fudgy brownies and peanut-butter confections. This hybrid dessert captures the nostalgic flavors of Midwest desserts while using a baking technique common in American home kitchens — layered bars that are easy to make and share at community gatherings.

Seasonal Adaptations

In winter, add 1/2 teaspoon ground cinnamon to the peanut butter layer for warmth, or sprinkle crushed peppermint on the ganache for a holiday twist. For summer gatherings, halve the ganache and top each chilled square with a dollop of whipped cream and fresh berries for refreshing contrast. For autumn, fold 1/2 cup finely chopped roasted pecans into the peanut butter filling to add seasonal nuttiness and texture.

Meal Prep Tips

Make the brownie base and peanut butter filling a day ahead; assemble and chill the next day for fresher ganache gloss. Store the filling in the refrigerator in an airtight container and let it sit at room temperature for 15–20 minutes before spreading so it becomes pliable. Use a serrated knife warmed under hot water and dried between cuts to get clean slices when serving a large group. Label and date frozen portions to rotate your dessert stash efficiently.

These Buckeye Brownies are one of those reliably loved treats that bring smiles every time. Their rich, familiar flavors and approachable technique make them a go-to for holidays, potlucks, and cozy nights in. Make them your own with a small tweak — a pinch of salt, a switch of chocolate — and enjoy watching friends and family disappear piece by piece.