Perfect for a picnic or a casual gathering, these salted peanut bars combine a chewy brown sugar crust, a gooey marshmallow center, and a crunchy peanut butter topping studded with salted peanuts and Rice Krispies. They’re easy to assemble, portable for outdoor events, and hold up well in a cooler on warm days since there’s no chocolate to melt.
Some recipes carry family memories, and this one always takes me back. My grandmother made these salted peanut bars for nearly every family event. Kept chilled in a cooler at outdoor gatherings, they disappeared within minutes, with cousins racing to grab a piece. The combination of textures and flavors is irresistible: a tender, brown sugar crust, soft, melted marshmallows in the middle, and a salty-sweet peanut butter topping made crunchy with Rice Krispies and peanuts.
Why peanut squares are ideal for an outdoor picnic
These bars are picnic-friendly for several reasons. They travel well in the pan they’re baked in, and because the topping contains no chocolate, they won’t turn into a sticky mess in mild heat. Pre-cut them at home and use the parchment overhang to lift them out for easy serving. Keep them in a cooler or refrigerator until ready to enjoy.
Making the brown sugar crust
The crust is thin, chewy, and flavored with brown sugar. To prepare it, combine flour, brown sugar, baking powder, baking soda, and salt in a medium bowl. Work in softened butter until the mixture is evenly moistened, then stir in the egg yolk and vanilla. The dough will be crumbly—that’s expected. Press the crumbs into a parchment-lined 9 x 9-inch pan, using a glass or measuring cup to compact the mixture into an even layer.
Bake the crust at 350°F for about 12–13 minutes, until it’s lightly golden. Remove it from the oven and immediately spread the mini marshmallows over the hot crust so they begin to melt and puff evenly. Return the pan to the oven for 1–2 minutes, just until the marshmallows puff; remove and set aside while you prepare the topping.
Tips for the toppings
The marshmallow layer is simply marshmallows, but timing matters for the topping. Follow these practical tips for smooth, even results:
- Pre-measure ingredients: Measure marshmallows, salted peanuts, and Rice Krispies before you begin the topping. Having everything ready makes the assembly quick and easy.
- Work quickly: Add the marshmallows as soon as the crust comes out of the oven so they puff without browning. When making the peanut butter topping, stir the nuts and cereal into the melted mixture and spread it over the marshmallows quickly—waiting too long can make the topping too firm to spread.
- Chill before cutting: For clean slices and the best texture, refrigerate the bars for at least 45 minutes before cutting.
How to store the bars
Use the parchment overhang to lift the chilled slab from the pan, cut into squares, then return the pieces to the pan for transport. Cover with foil and keep in a refrigerator or cooler until serving. Leftovers keep well for 4–5 days when refrigerated in an airtight container or wrapped pan. For longer storage, freeze them in a single layer or separated with wax paper.
Freezing instructions
These bars freeze nicely for one to two months when tightly wrapped or stored in an airtight container. Thaw in the refrigerator or let them sit at room temperature for 20–30 minutes before serving so they soften slightly and are easy to bite.
Salted Peanut Bars
These bars yield about 16 squares and are a salty, peanut-butter-forward dessert with a chewy brown sugar base and a pillowy marshmallow layer.
Salted Peanut Bars
Ingredients
Crust
- 3/4 cup flour
- 1/3 cup packed brown sugar
- 1/4 teaspoon baking powder
- 1/8 teaspoon baking soda
- 1/2 teaspoon salt
- 4 tablespoons unsalted butter, softened
- 1 teaspoon vanilla
- 1 egg yolk
Filling
- 2 cups mini marshmallows
Topping
- 1/3 cup corn syrup
- 2 tablespoons unsalted butter
- 1 teaspoon vanilla
- 1 cup peanut butter chips
- 1 cup salted peanuts
- 1 cup Rice Krispies
Instructions
Crust
- Preheat oven to 350°F. Line a 9 x 9-inch pan with parchment, leaving an overhang on two sides.
- Combine flour, brown sugar, baking powder, baking soda, and salt in a medium bowl. Add softened butter and work it into the dry ingredients until evenly mixed.
- Stir in the egg yolk and vanilla. The mixture will be crumbly—press it firmly into the prepared pan using a cup or glass.
- Bake 12–13 minutes until lightly golden. Remove from oven and immediately distribute the mini marshmallows over the crust. Return to the oven 1–2 minutes until they puff; then remove and prepare the topping.
Topping
- In a medium saucepan over medium heat, combine corn syrup, butter, peanut butter chips, and vanilla. Stir until just melted and smooth.
- Stir in the salted peanuts and Rice Krispies quickly until combined.
- Using two spoons, dollop the peanut topping over the marshmallows and gently spread to cover completely.
- Chill in the refrigerator, covered, for at least 45 minutes. Once firm, lift from the pan with the parchment overhang and cut into squares with a sharp knife.
Notes
- Store in the refrigerator or a cooler until ready to serve.
- Freeze for up to 2 months in an airtight container, separated with wax paper if needed.
Nutrition
Enjoy these salted peanut bars at your next picnic—just chill before slicing for the best texture.