Peanut Butter Marshmallow Cookie Bars Recipe

Indulge in these irresistible Peanut Butter Marshmallow Cookie Bars! A holiday favorite, this recipe delivers rich, gooey perfection with a delightful peanut butter crunch. Get ready for a flavor explosion that will have everyone asking for more! Perfect for cookie swaps, holiday gatherings, or any time you crave a decadent treat.

Prep Time 20 mins

Cook Time 55 mins

Calories 236.1 kcal

Protein 7g

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The Forktionary Kitchen Team

Adapted from Food.com, then tested & standardized by Forktionary.

Ingredients for Peanut Butter Marshmallow Cookie Bars

Yellow Cake Mix With Pudding
1/2 cup (1 stick) margarine, softened (for crust) and 1/4 cup (1/2 stick) margarine (for topping)
1 large egg
3 cups mini marshmallows
1/2 cup light corn syrup
1 teaspoon vanilla extract
1 cup peanut butter chips
3 cups Rice Krispies cereal (or similar crispy cereal)

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How to Make Peanut Butter Marshmallow Cookie Bars

Preheat oven to 350°F (175°C).
Crust: In a large bowl, combine 1 box (15.25 oz) yellow cake mix, 1/2 cup (1 stick) margarine, softened, and 1 large egg.
Mix until the mixture resembles coarse crumbs.
Press the crumb mixture firmly into the bottom of an ungreased 13x9 inch baking pan.
Bake for 15-20 minutes, or until the crust is lightly golden brown.
Remove from oven and immediately sprinkle evenly with 3 cups mini marshmallows.
Return to the oven for 1-2 minutes, or until the marshmallows are lightly puffed.
Topping: In a medium saucepan over medium heat, combine 1/2 cup light corn syrup, 1/4 cup (1/2 stick) margarine, 1 teaspoon vanilla extract, and 1 cup peanut butter chips.
Stir frequently until the chips are melted and the mixture is smooth.
Remove from heat and stir in 3 cups Rice Krispies cereal (or similar crispy cereal).
Immediately spread the peanut butter topping evenly over the marshmallow layer.
Refrigerate for at least 30 minutes to allow the bars to set completely before cutting into squares.

Nutrition Information (Approximate per serving)

Sodium

9 g

Sugar

84g

Fat

14g

Carbs

11g

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Sweets & Sides Desserts The Americas American Southern Vegetarian Fall Recipes Holiday Recipes Baking

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Frequently Asked Questions

How long does it take to make Peanut Butter Marshmallow Cookie Bars?

Peanut Butter Marshmallow Cookie Bars takes about 75 minutes from start to finish — roughly 20 minutes to prepare and 55 minutes to cook.

How many calories are in Peanut Butter Marshmallow Cookie Bars?

Peanut Butter Marshmallow Cookie Bars has approximately 236.1 calories per serving, with about 7 g protein, 11 g carbohydrates and 13 g fat.

What ingredients do I need for Peanut Butter Marshmallow Cookie Bars?

The key ingredients for Peanut Butter Marshmallow Cookie Bars are Yellow Cake Mix With Pudding, Margarine, Egg, Mini Marshmallows, Corn Syrup, Vanilla. See the full list with measurements above.