Pro tips and easy variations
Sifting the cocoa and flour with the leavening and salt is the secret to avoiding dry pockets and ensuring a smooth batter, especially in recipes with a lot of cocoa.
If the marshmallow fluff is difficult to spread, warm it briefly in the microwave and either pipe or spoon it in dollops rather than trying to smear a thick layer; this prevents dragging the peanut butter and tearing the bottom brownie layer.
Simple variations:
- Swirl instead of layer: Instead of a full center layer, spread all the brownie batter in the pan, then dollop peanut butter and fluff on top and gently swirl with a knife for a marbled effect.
- Add crunch: Sprinkle chopped peanuts or mini peanut butter cups over the peanut butter layer for extra texture and peanut flavor.
- Extra chocolate: Fold additional chocolate chips into the batter or drizzle melted chocolate over the cooled brownies.
Storage and make‑ahead
These brownies keep their fudgy texture well and are great for making ahead.
- Room temperature: Store fully cooled brownies in an airtight container at room temperature for up to 3 days. Layer with parchment paper if stacking so the marshmallow doesn’t stick.
- Refrigerator: For slightly firmer layers, refrigerate in a sealed container; bring to room temperature or warm briefly before serving if you prefer a softer texture.
- Freezer: Wrap individual squares tightly in plastic wrap and place in a freezer bag or container. Freeze for up to about 2 months. Thaw at room temperature or gently warm in the microwave for a just‑baked feel.
FAQ
Can I use natural peanut butter?
Natural peanut butter is thinner and oilier and can separate or bake differently, so regular creamy peanut butter is recommended for the most stable layers. If you use natural, stir it very well and expect a slightly different texture.
Can I skip the espresso powder?
Yes. Espresso powder simply enhances the chocolate flavor; omitting it will not affect the structure. If you don’t have it, you can leave it out or replace with a small amount of instant coffee.
How do I keep the brownies fudgy, not cakey?
Measure flour carefully, don’t over‑mix once you add the dry ingredients, and avoid over‑baking. Pull the brownies as soon as the edges are set and the center has just a slight jiggle and moist crumbs on a tester.
Can I halve the recipe?
Yes, you can halve the ingredients and bake in an 8×8 or 9×9 pan, adjusting the bake time down slightly and checking earlier for doneness.
Conclusion and call to action
Fluffernutter Brownies turn a classic fudgy brownie into a nostalgic peanut butter–and–marshmallow treat with a gooey center and crackly top. They’re rich enough for celebrations but easy enough for any weekend bake, and they slice into stunning layered squares that always disappear fast.