Amazing blondie-cookie bar that tastes like a cross between a fluffernutter sandwich and a peanut butter blossom cookie! Hershey's® chocolate makes it taste like a peanut butter blossom cookie. Definitely underbake!

Recipe Summary

15 mins
15 mins
30 mins
1 hr
1 9x13-inch baking dish


Original recipe yields 16 servings
The ingredient list now reflects the servings specified
Ingredient Checklist


Instructions Checklist
  • Preheat oven to 350 degrees F (175 degrees C). Grease a 9x13-inch baking dish.

  • Beat butter, brown sugar, peanut butter, and white sugar together in a bowl until smooth and creamy. Add egg and egg yolk and mix gently. Gradually stir in flour, baking soda, and salt just until batter is mixed. Gently fold chocolate chips and marshmallows into batter. Spread batter into the prepared baking dish.

  • Bake in the preheated oven until edges are lightly browned, 15 to 20 minutes. The center will set as it cools. Cool completely before slicing, about 30 minutes.

Nutrition Facts

431 calories; protein 6.2g 13% DV; carbohydrates 51.2g 17% DV; fat 24.6g 38% DV; cholesterol 54.9mg 18% DV; sodium 305.8mg 12% DV. Full Nutrition

Reviews (14)

Read More Reviews

Most helpful positive review

Rating: 5 stars
these bars w were great. my family eat them up in a day! I used dark chocolate chips which is a family favorite. we will be making these many times going forward. Read More
18 Ratings
  • 5 star values: 16
  • 4 star values: 2
  • 3 star values: 0
  • 2 star values: 0
  • 1 star values: 0
Rating: 5 stars
My family loved this! I added a 1/2c if peanut butter chips and accidentally doubled the marshmallows. We had to cook it longer for about 45 minutes total. It browned nicely. But was still a little gooey in the middle after 2 hours of setting. By day 2 it was set better. Will continue making!!! Thanks!! Read More
Rating: 5 stars
Super easy to make and delicious! I followed the recipe as written. Everyone loved them! Read More
Rating: 5 stars
Melt in your mouth delicious! Under baking is good advice - once there marshmallows look slightly browned I took it out of oven. Will definitely make these again. Read More
Rating: 4 stars
What a fun recipe! I used natural peanut butter and loved the taste of the butter brown sugar peanut butter and sugar mix. So delicious. Once cooled this was very easy to cut into bars. It was a tiny bit crumbly but it could be because there were too many marshmallows getting in the way of the batter adhering nicely. Still so good--took this to the office today for a potluck and all the bars were devoured and the plate picked clean before the main dishes were even dished into. Read More
Rating: 5 stars
The first day I made these I would've rated them 5 stars for flavor but 4 stars because they were very crumbly and fell apart. However by day 2 they held together wonderfully! Like a peanut butter s'more cookie! My family couldn't get enough! Read More
Rating: 5 stars
Delicious! My only advice would be to make sure they're totally cooled before you cut them into bars and serve them. Read More
Rating: 5 stars
Oh baby! I've made these twice now. I don't think they can be "overbaked" as (the 2nd time I made them) I forgot to set a timer and after about 22 minutes blasted them out of the oven. They are wonderful! Also, this time around, I used 1 C chocolate chips and 1 C butterscotch chips. Threw them in the fridge for 20 min since we couldn't wait to cut into them. Yumm-O! Read More
Rating: 5 stars
Delicious!! Cool completely before cutting. Read More
Rating: 4 stars
Having grown up on Fluffernutters this recipe went in my favorites as soon as I saw it. I attempted to make it gluten free by using Cup for Cup gluten free all purpose flour. I baked for an additional 10 minutes and I think it could have baked longer as it was still very undone in the middle and it ultimately fell while cooling. My family still ate it and liked the cookie doughiness of it. I agree with Diana and the marshmallows could be cut back. I will be making it again but with minor adjustments. Read More