Ooey Gooey Peanut Butter S’mores Bars
A fun take on a traditional s'mores. Homemade marshmallows and peanut butter stuffed between chocolate graham cracker and smother in chocolate.
The Story Behind Peanut Butter S’mores Bars
I’m a sucker for anything with marshmallows and these peanut butter s’mores bars are no exception. Back when we (by we, I mean my husband and I) were in business school out at Stanford, we would get together often for fire pits with our good friends.
Stanford is a magical place where everyone’s back doors open to a gated, communal courtyard, and playground. So after all of the little ones were in bed, everyone would bring their camp chairs and baby monitors and gather around a fire pit. My neighbors always had the makings for s’mores on hand, so you know I was always game for a fire pit night.

One of the things I discovered when we were outside doing fire pits was that you can totally replace the traditional Hershey’s bar with Reese’s Peanut Butter cups. Say what? How was I 28-years-old and when discovering that?
About a year ago, I was over at my bestie’s house and noticed she had a bag of the s’mores mix you can buy at Costco. She pulled it out for me to try and then wound up sending it home with me. Bad mistake! I finished the bag off the next day. I’ve only allowed myself to buy that mix one more time, and let’s say it didn’t end very well either. Or it did. My motto is, “I might as well eat it all so it’s not in the house anymore.” Anyone else think that way?

Since we don’t have a fire pit, and don’t make s’mores often, I decided I wanted to come up with a treat that mimicked an ooey gooey marshmallowy s’more. The thing I love about the s’mores mix you can buy at Costco is that each piece is covered in chocolate. That was a must for me. Yummy ingredients covered in chocolate. How can you go wrong with that? Although, I do know that everyone has different levels of chocolate love, so dipping the entire bar in chocolate may not be for you. You could do half, you could dip just the corners, or you can really go for it and dunk the whole thing.

Just like a fire pit roasted s’more, these peanut butter s’mores are a bit messy! How can it not be when there is gooey marshmallow involved? The marshmallow isn’t really the messy part here, though. These aren’t M&M’s, so they are going to melt in your hands as well as your mouth since they are covered in chocolate.
Additional Recipes Similar to Peanut Butter S’mores Bars
- Chocolate Peanut Butter Rice Krispie Treats
- Peanut Butter Cookies with Sea Salt Dark Chocolate Caramels
- Samoa Rice Krispies

Peanut Butter S’mores Bars
Ingredients
- 1 box chocolate graham crackers
- ¼-½ cup your favorite peanut butter
- 2 cups sugar
- 1 cup cold water divided
- 2 packets Knott’s gelatin (.25 oz each)
- 1 tsp vanilla
- 2-3 cups of semisweet chocolate chips
Instructions
- In the bowl of an electric mixer fitted with a whisk attachment, dump in 1/2 cup water with the two envelopes of gelatin. Make sure the water is cold as this is what will activate the gelatin. Give it a quick mix and then let it sit.
- To make the marshmallow filling, heat the sugar and remaining 1/2 cup of water on the stovetop. You will need a candy thermometer to make this correctly. Heat the mixture to 235 degrees and remove from heat. This will take about 5 minutes.
- Once the sugar has reached the correct temperature, remove it from the heat. With the mixer on low speed, slowly add the hot liquid sugar mixture in a steady stream. The gelatin will melt, which is good and what you want.
- Gradually turn the speed of the mixer up and mix until you get medium stiff peaks. It will look like meringue. As it cools, which it does quickly, it becomes more marshmallowy in texture.
- To assemble the bars, smear as much or as little peanut butter you would like on one side of graham cracker. Use a piping bag, or a ziploc bag with the corner cut off, to squeeze the marshmallow filling in the middle of each cracker. You can be as generous as you’d like here. Just keep in mind that it will squeeze out some once you put the top cracker on.
- Cover the marshmallow filling with a graham cracker top.
- Melt the chocolate chips in a microwave safe bowl. Dip the top half of each bar in the chocolate. Place on a cookie sheet lined with parchment paper. Once all are dipped, place in the fridge or freezer to chill. Once they are chilled and hardened, dip the other side.
- Store in the fridge until ready to eat.