Classic Peanut Butter Cookie Bars with Frosting

  • In a separate bowl, whisk together flour, baking powder, and salt.
  • Gradually stir the dry mix into the wet ingredients using a rubber spatula. The batter will be thick that’s perfect.

3: Bake the Bars

    • Preheat your oven to 350°F (175°C).
    • Spread the batter evenly into a greased or parchment lined 9×13-inch pan.
    • Bake for 25-28 minutes or until the top is golden and a toothpick inserted in the center comes out clean.
    • Let the bars cool completely in the pan before frosting. This step matters if they’re warm, the frosting will melt!

 

Make the Peanut Butter Frosting

1: Cream the Base

  • In a mixing bowl, beat together peanut butter and softened butter until smooth and fluffy.

2: Add Sugar and Milk

  • Gradually mix in the powdered sugar. Add milk a tablespoon at a time to reach your desired creamy consistency.
  • Stir in the vanilla extract for that warm, familiar flavor.

3: Frost the Bars

  • Use a spatula to generously spread the frosting over the cooled bars.
  • Let the frosting set at room temperature for 20-30 minutes before slicing.
Soft peanut butter cookie bars with frosting on top
Chewy, nostalgic peanut butter bars like the lunch lady used to make

Serving Suggestions

  • Cut into squares or rectangles depending on how many guests you’re serving.
  • Top with chopped roasted peanuts or mini chocolate chips for a little flair.
  • Serve chilled for a firmer bite, or room temperature for soft, gooey nostalgia.

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