These soft, gooey, peanut butter cookie bars are the perfect sweet and salty treat! Full blog post coming soon.
Fluffernutter Cookie Bars
These soft, gooey, peanut butter cookie bars are the perfect sweet and salty treat!* Be sure to refer to the full blog post on my website for instructions & baking times!
Print
Rate
Servings: bars
Ingredients
- ½ cup unsalted butter softened
- ¾ cup creamy peanut butter
- ¾ cup light brown sugar
- ¼ cup granulated sugar
- 1 large egg
- 1 egg yolk i.e. you will be using 1 whole egg + 1 extra egg yolk
- 1 teaspoon vanilla extract
- ½ teaspoon baking soda
- ¼ teaspoon salt
- 1 tablespoon cornstarch optional, will give a more chewy texture
- 1 ½ cups all-purpose flour
- 1 cup semi-sweet chocolate chips (I did half chocolate chips & half chopped Reeses cups)
- 1 cup mini marshmallows
Before you begin! If you make this, will you do me a huge favor and leave a review and rating letting me know how you liked this recipe? This helps my small business thrive so I can continue providing free recipes and high-quality content for you.
Instructions
- Preheat oven to 350ºF. While preheating, be sure to read tips & tricks in post for recipe success.
- In a medium-sized mixing bowl, beat the softened unsalted butter (½ cup, i.e. 1 stick) and peanut butter (¾ cup) on medium speed for 20-30 seconds until combined.
- Add in the light brown sugar (¾ cup) and granulated sugar (¼ cup) and continue beating on medium for another 20-30 seconds until creamy. Do not over mix.
- While the mixer is on low, add in the egg (1 large), extra egg yolk (1 large), vanilla extract (1 teaspoon), baking soda (½ teaspoon), salt (¼ teaspoon), and cornstarch (1 tablespoon). Stir until combined. Slowly add in all-purpose flour (1 ½ cups) and mix until just incorporated.
- Mix in chocolate chips (1 cup) and marshmallows (1 cup).
- Grease and line a 9×13 light-colored metal pan with parchment paper (I like to create a parchment sling so I can lift the bars out of the pan to cut). Spread dough into an even layer in pan.
- If desired, press on extra chocolate chips or peanut butter cups into the top.
- Bake for 16-18 minutes or until edges are lightly brown, marshmallows are lightly toasted, and the center no longer looks wet (some ovens may need more or less time). Allow the bars to cool for at least 30 minutes before cutting, as they will fall apart when warm. For the best slice, I recommend refrigerating the bars for about 1 hour before slicing.
Last Step! Please leave a review and rating letting me know how you liked this recipe! This helps my small business thrive so I can continue providing free recipes and high-quality content for you.
Notes
Storage: Store in an airtight container for up to 5 days (although they're best within 3 days for ultra softness!).
Freezing: Store in an airtight container or freezer ziploc bag for up to 1 month. For optimal freshness, I recommend wrapping the individual bars in plastic wrap before placing in container.
Nutrition
Calories: 403kcal | Carbohydrates: 45g | Protein: 7g | Fat: 23g | Saturated Fat: 10g | Polyunsaturated Fat: 3g | Monounsaturated Fat: 8g | Trans Fat: 1g | Cholesterol: 51mg | Sodium: 179mg | Potassium: 221mg | Fiber: 2g | Sugar: 27g | Vitamin A: 285IU | Calcium: 37mg | Iron: 2mg
Gina says
These were so quick and easy to make. The peanut butter taste really comes out in the bars. The only thing mine aren’t as gooey as the picture. Maybe I should’ve added more than a cup of mini marshmallows.
Jean says
They turned out amazing!! So gooey and so much delicious flavors!
Melissa says
So glad that you enjoyed this recipe Jean, thank you for taking the time to leave a review!