Peanut butter marshmallow cookies use a flourless dough made from creamy peanut butter, sugar, an egg, vanilla, baking soda, and salt. Small marshmallow pieces are folded into that base before the portions go onto parchment. The marshmallows soften and spread in the oven, so keep them tucked into the dough where possible. Let the cookies firm on their trays before moving them; they are fragile straight from the oven.
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Why This Recipe Works
Peanut butter supplies the fat and much of the structure in peanut butter marshmallow cookies. The egg helps bind the mixture as it bakes, while sugar sweetens and affects spread. There is no missing flour ingredient to add automatically.
Marshmallows behave differently from chocolate chips. They can melt into sticky pockets or flow out where they touch the hot tray. Small pieces, parchment, and generous spacing make that easier to manage. A soft center is expected initially, but the cookies need a baked edge and a surface that is no longer raw.
Ingredients for Peanut Butter Marshmallow Cookies
Use a conventional creamy peanut butter that is well mixed and holds its consistency, rather than a jar with a separated pool of oil. Measure one cup of it and one cup granulated sugar. The single large egg is the only egg in this batch.
Peanut butter marshmallow cookies use one cup of mini marshmallows or small pieces cut from larger marshmallows. Keep the quantity measured instead of adding an unlimited handful. The dough does not include wheat flour, but that fact alone does not verify a gluten-free result for every brand or kitchen.
Main ingredients
- 1 cup creamy peanut butter (conventional smooth peanut butter, thoroughly mixed)
- 1 cup sugar
- 1 large egg
- 1 teaspoon vanilla extract
- 1 cup mini marshmallows (or cut large marshmallows into small pieces)
- 1/2 teaspoon baking soda
- 1/4 teaspoon salt
How to Make Peanut Butter Marshmallow Cookies
Heat the oven to 350°F and line two baking sheets with parchment. Stir the peanut butter, sugar, egg, vanilla, baking soda, and salt until the mixture is even. Scrape the bowl so pockets of plain peanut butter do not remain underneath the dough.
Fold in the measured marshmallow pieces. Divide the mixture into about 24 small, reasonably equal portions, using a rounded tablespoon as a starting guide rather than making twelve very large mounds. Arrange twelve pieces per tray, spaced about two inches apart. Press any exposed marshmallow on the bottom back into the dough.
Bake peanut butter marshmallow cookies one tray at a time for about 10–12 minutes. Look for set edges and a top that no longer looks wet; exposed marshmallow may color before the rest of the cookie. Do not wait for every surface to become dark brown. Remove the first tray, let it sit at least five minutes, and bake the second tray.
Use a thin spatula to lift cooled, firming cookies to a rack. If a marshmallow has flowed out, let the sticky patch set before trying to scrape it away. The total bake time listed allows two consecutive twelve-minute trays, not a twelve-minute bake for the entire batch.
How to Serve
Serve peanut butter marshmallow cookies after they have cooled enough to hold together. Twenty-four small cookies make a convenient sharing batch; larger scoops produce fewer pieces and require a separate doneness check. A small serving plate with parchment under the cookies helps prevent sticky marshmallow edges from adhering to it.
Storage
Store cooled peanut butter marshmallow cookies in an airtight container for up to three days at room temperature. Separate stacked layers with parchment and keep them away from a hot sunny counter. Freeze fully cooled cookies in a sealed container for up to two months, then thaw while covered before separating the layers.
Preparation reference: King Arthur Baking, Flourless Peanut Butter Cookies. Follow FoodSafety.gov cooking temperatures.
Tips and Variations
Bake a small first tray if you are unsure how your peanut butter behaves. If it spreads heavily, chill the remaining portions until firmer and use a fully cooled pan for the next batch. Adding flour changes the base recipe, so do not treat it as the first automatic correction.
For peanut butter marshmallow cookies, avoid replacing small pieces with one oversized marshmallow in each dough mound. The large center melts differently and can leave a cavity. Cut larger marshmallows into small pieces before measuring the cup, and spread those pieces through the dough.
Frequently Asked Questions
Do peanut butter marshmallow cookies need flour?
No. This measured base is flourless; peanut butter and egg provide its structure.
Why are the cookies fragile when hot?
The dough and melted marshmallows need time to set. Leave the cookies on the tray at least five minutes before lifting them.
Can I use large marshmallows?
Yes, if they are cut into small pieces before measuring. Do not use one large whole marshmallow as a direct substitute.
Can I use oily natural peanut butter?
It can change spread and texture. A conventional, well-mixed creamy peanut butter is the clearest match for this formula.
How do I avoid sticky stacks?
Cool completely and place parchment between layers. Never seal warm cookies in the container.
More Recipes to Try
- Easy 3 Ingredient Brown Sugar Cookies
- Chewy Chocolate Chip Cookies
- Soft and Chewy Gingerbread Cookies
- Lemon Bars with Shortbread Crust
Peanut Butter Marshmallow Cookies
Ingredients
Main ingredients
- 1 cup creamy peanut butter conventional smooth peanut butter, thoroughly mixed
- 1 cup sugar
- 1 large egg
- 1 teaspoon vanilla extract
- 1 cup mini marshmallows or cut large marshmallows into small pieces
- 1/2 teaspoon baking soda
- 1/4 teaspoon salt
Instructions
- Cover two baking sheets with parchment and preheat to 350°F.
- Stir peanut butter, granulated sugar, egg, vanilla, baking soda, and salt into an even dough.
- Fold in 1 cup small marshmallow pieces. Divide into roughly 24 small portions and space twelve on each sheet.
- Tuck protruding bottom marshmallow pieces into the dough. Bake each tray 10–12 minutes, until edges and top are set; watch exposed marshmallows.
- Let each tray stand at least 5 minutes, then lift firming cookies to a rack. Cool fully before stacking.
