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Black Widow Peanut Butter Bars Recipe

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4.1 from 11 reviews

Delightfully festive Black Widow Peanut Butter Bars combine a rich peanut butter cookie base with a luscious chocolate frosting, topped with a whimsical marshmallow spider web and adorable chocolate spider decorations. Perfect for Halloween parties or themed gatherings, these bars boast a balance of sweet, nutty, and chocolatey flavors with a fun, spooky presentation.

Ingredients

Cookie Base

  • 1 1/2 sticks (3/4 cup) salted butter
  • 2 cups creamy peanut butter
  • 3/4 cup light brown sugar
  • 1/4 cup granulated sugar
  • 2 large eggs, at room temperature
  • 1 tablespoon vanilla extract
  • 2 cups all-purpose flour
  • 1 teaspoon baking powder
  • 1/2 teaspoon kosher salt

Peanut Butter Layer

  • 1 stick (1/2 cup) salted butter, at room temperature
  • 1/2 cup peanut butter

Chocolate Frosting

  • 2–3 cups powdered sugar
  • 1/2 cup cocoa powder
  • 2 teaspoons vanilla extract
  • 1/4 cup warm milk (plus extra as needed)

Decoration

  • Marshmallows (for melted web)
  • Whoppers (for spider bodies)
  • Candy eyes
  • Melted chocolate (for legs and eyes)
  • Black or silver sprinkles (for spider leg decoration)
  • Small plastic spiders (optional)

Instructions

  1. Preheat and Prepare Dish: Preheat your oven to 350°F (175°C). Line a 9×13-inch baking dish with parchment paper for easy removal and cleanup.
  2. Make Cookie Base Dough: In a microwave-safe bowl, melt together the 3/4 cup salted butter and 1/2 cup peanut butter, stirring every 30 seconds until fully melted. Stir in the light brown sugar, granulated sugar, eggs, and vanilla extract until smooth. Gradually add the all-purpose flour, baking powder, and kosher salt, stirring until a dough forms.
  3. Bake Base: Spread or press the dough evenly into the prepared dish. Place in the oven and bake for 18-22 minutes, or until the center is just set (do not overbake). Remove from the oven.
  4. Add Peanut Butter Layer and Cool: Dollop tablespoon-sized spoonfuls of the remaining 1/2 cup peanut butter over the warm bars. Lightly spread into an even layer. Allow the bars to cool completely in the pan.
  5. Prepare Chocolate Frosting: In the bowl of a stand mixer, combine the 1/2 cup softened butter, 2 cups powdered sugar, cocoa powder, vanilla extract, and 1/4 cup warm milk. Beat until smooth, adding extra warm milk as needed to achieve a thick but drizzly consistency. Adjust sweetness by adding more powdered sugar if desired.
  6. Frost Bars: Spread the chocolate frosting evenly over the cooled bars. Let the frosting set for about 1 hour.
  7. Create Marshmallow Spider Web: Melt marshmallows in the microwave in 30-second intervals, stirring between each until smooth and fully melted. Let cool 3-5 minutes, then use your hands to stretch and pull the melted marshmallow over the bars forming a spider web pattern, extending in multiple directions. The process is intentionally messy and fun.
  8. Make Chocolate Spiders: Line a baking sheet with parchment paper. Transfer melted chocolate to a piping bag or ziplock bag with a fine tip. Pipe two small dots of chocolate about 1/3 inch in diameter side by side on the parchment. Place one Whopper on each dot. Add 2-3 legs on each side of the Whopper by piping thin lines of chocolate. Sprinkle legs with black or silver sprinkles. Add tiny dots of chocolate near the Whopper for eyes and place candy eyes if available. Freeze the spiders on the baking sheet for 15 minutes to harden.
  9. Decorate Bars: Gently peel the hardened chocolate spiders from the parchment and arrange them on top of the spider web decorated bars. Add small plastic spiders if desired for extra spooky effect.
  10. Serve and Store: Slice into bars and serve. Store leftovers in a cool, dry place; they can be refrigerated or kept at room temperature.

Notes

  • Allow the bars to cool completely before frosting to prevent melting the frosting.
  • For best results, use room temperature eggs and butter to improve mixing consistency.
  • If marshmallows become too sticky while making the web, lightly dust your hands with powdered sugar.
  • The chocolate spiders can be made ahead and stored frozen until ready to use.
  • If desired, substitute gluten-free flour for a gluten-free version, adjusting moisture as necessary.
  • Store bars in an airtight container to maintain freshness for up to 4-5 days.

Find it online: https://lauracooks.com/black-widow-peanut-butter-bars-recipe/