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If you’re the kind of person who believes dessert should be both wildly comforting and sneakily sensible, allow me to introduce your new best friend: Peanut Butter Chocolate Chunk Marshmallow Bars. These bars take everything you love about childhood campfire s’mores and elevate them with a little adult-level fun (think natural peanut butter, a modest amount of dark chocolate, and marshmallow goo). They’re gooey, chewy, slightly salty, and just sweet enough to make you close your eyes and sigh. Also: marshmallows. Need I say more?

Why these bars work

Flavor Balance: Creamy peanut butter, lightly sweet marshmallow, and semi-sweet chocolate chunks create a floral-yet-funky harmony. A pinch of sea salt pulls all the notes together.
Texture Party: Chewy oat base, soft marshmallow center, and melty chocolate pockets give you something to look forward to in every bite.
Health-forward Swaps: Flour and natural peanut butter add fiber and protein so these hit the snack/dessert sweet spot—guilt reduced, satisfaction intact.

Baking notes (read before you start)

If you hate sticky gooey things on your fingers but love them on your face, line the pan with parchment and let the finished bars chill slightly before slicing.
Want them vegan? Use a flax egg, maple syrup, vegan marshmallows, and vegan chocolate.
For extra crunch, fold in chopped nuts or toasted seeds. Add a sprinkle of flaky sea salt on top for sophistication.

Peanut Butter Chocolate Chunk Marshmallow Bars

Yield: 12

Author: The Skinny Fork (Amanda Plott)

Prep time: 15 MinCook time: 30 MinInactive time: 20 MinTotal time: 1 H & 5 M

These bars take everything you love about childhood campfire s’mores and elevate them with a little adult-level fun!

Ingredients

1/2 C. Butter, Room Temperature
1/2 C. Creamy Peanut Butter
1 C. Brown Sugar
2 Whole Large Eggs, Room Temperature
2 Tsp. Vanilla Extract
2 1/2 C. Flour
1/2 Tsp. Baking Soda
1 Tsp. Salt
1/2 C. Semi-Sweet Chocolate Chunks (or Chocolate Chips)

Peanut Butter Frosting

1/4 C. Creamy Peanut Butter
1/2 C. Powdered Sugar
1 1/2 Tbsp. Butter, Room Temperature
1 Tbsp. Heavy Cream
1/4 Tsp. Vanilla Extract
5 Oz. Marshmallow Fluff

Instructions

Preheat the oven to 350 degrees F. and line a 8x8" or 9x9" baking dish with parchment paper.
In the base of a stand mixer, beat together the 1/2 C. Butter, 1/2 C. Creamy Peanut Butter, 1 C. Brown Sugar, 2 Whole Large Eggs, and 2 Tsp. Vanilla Extract.
Add in the 2 1/2 C. Flour, 1/2 Tsp. Baking Soda, and 1 Tsp. Salt until just incorporated.
Fold in the 1/2 C. Semi-Sweet Chocolate Chunks.
Transfer the mixture to the prepared baking dish and press it down to an even layer. Place it in the oven to bake for 25 minutes.
While that's baking, make the frosting. Place the 1/4 C. Creamy Peanut Butter, 1/2 C. Powdered Sugar, 1 1/2 Tbsp. Butter, Room Temperature, 1 Tbsp. Heavy Cream, and 1/4 Tsp. Vanilla Extract into the clean base of a stand mixer. Beat until light and fluffy.
Once the bars are done in the oven, remove them and set aside to cool for about 20-30 minutes.
With the bars cooled, top them with the Peanut Butter Frosting.
Top that with the 5 Oz. Marshmallow Fluff.
Enjoy right away or set in the fridge to chill and firm things up if desired.

Recommended Products

SKIPPY Creamy Peanut Butter

Nestle Toll House Semi Sweet Chocolate Chunks

Jet-Puffed Marshmallow Creme

Nutrition Facts

Calories

456

Fat (grams)

22 g

Sat. Fat (grams)

10 g

Carbs (grams)

61 g

Fiber (grams)

2 g

Net carbs

58 g

Sugar (grams)

35 g

Protein (grams)

8 g

Sodium (milligrams)

405 mg

Cholesterol (grams)

53 mg

Nutritional Claims: Kidney Friendly • Tree Nut Free • Soy Free • Fish Free • Shellfish Free • Pork Free • Red Meat Free • Crustacean Free • Celery Free • Mustard Free • Sesame Free • Lupine Free • Mollusk Free • Alcohol Free