Peanut Butter S'mores Chocolate Chip Cookie Bars

After trying my Salted Caramel Chocolate Chip Cookie Bars, I was floored to try and do more with the recipe. With Memorial Day coming up and the family BBQs that entails, I thought what more appropriate than a s'mores bar? And after looking around and seeing this recipe I thought peanut butter would be a great addition. This recipe makes a lot (which totally isn't an issue) but if you want to be conservative, you can half it and use an 11 x 7 baking dish. Try them out for your next BBQ and let me know what you think!

Prep Time: 25 Minutes

Cook Time: 30 Minutes

*Note: This recipe fills a 9 x 13 AND an 8 x 8 baking dishes.


5 Cups All Purpose Flour

2 tsp. Baking Soda

2 tsp. Salt

2 Cups Butter, softened

1 ½ Cups Brown Sugar

1 ½ Cups White Sugar

4 Eggs

3 tsp. Vanilla Extract

8 -12 oz. Milk Chocolate Chips

8 -12 oz. Semi-Sweet Chocolate Chips

2 – 7 oz. Jars of Marshmallow Fluff

2.5 Cups Peanut Butter

½ Cup Powdered Sugar

1 Cup Sweetened Condensed Milk

                               - OR -

¾ Cup Heavy Whipping Cream


  1. Position rack to the center of the oven and preheat to 325°
  2. Place flour, baking soda, and salt in large mixing bowl and whisk together.
  3. In bowl of mixer beat together butter and sugars until smooth using paddle attachment. Beat in eggs and vanilla until smooth.
  4. Gradually add flour mixture until well combined.
  5. Transfer to large bowl and mix in the chocolate chips with a spoon or spatula.
  6. Grease a 9 x 13 baking dish. This recipe will also fill a small 5 x 7 baking dish so grease a smaller dish as well.
  7. Split the dough and press a little under half of it into the bottom of the baking dish(es).
  8. Place peanut butter, sweetened condensed milk (or heavy whipping cream), and powdered sugar in bowl of a stand mixer equipped with a paddle attachment. Mix until well combined.
  9. Spread peanut butter mixture over cookie dough layer.
  10. Using a spatula, scoop marshmallow fluff onto peanut butter layers. Wet hands generously with warm water and use to spread out fluff. The fluff won’t stick to your hands when they are wet.
  11. Spread remaining dough out onto two pieces of wax paper into the shape of each pan. A tip to get the size right: on the back of the wax paper, trace the shape of the pan with a marker. Place the marker side facedown on the counter.
  12. Place in oven and cook for 30 – 35 minutes until golden brown. Marshmallow fluff will bubble up and form peaks in the cookie dough, don’t let peaks get too brown.
  13. Remove and let cool. Cut into squares and enjoy!

Downloadable Peanut Butter S'mores Chocolate Chip Cookie Bars Recipe