These Peanut Butter Marshmallow Squares are a quick, nostalgic no-bake treat that hits sweet, salty, and chewy all at once. I make them when I want something fuss-free that still feels special — they come together in about 15 minutes on the stove and then chill. If you like simple peanut-butter-forward snacks, you might also enjoy this 3-ingredient peanut butter balls I tested alongside these squares.
Why Make This Recipe
- Fast and reliable: most of the work is melting and stirring, then chilling — perfect for busy evenings or last-minute desserts.
- Crowd-pleaser texture: soft marshmallow and creamy peanut butter combine with crumbs for a satisfying chew.
- No oven required: ideal for hot days, dorm cooking, or when you don’t want to heat the kitchen.
- Flexible base: you can switch the crumb or add chocolate for holidays and parties. I love this recipe because it’s forgiving — a small tweak in peanut butter or crumbs still yields great bars.
- Kid-friendly and portable: easy to pack for school lunches or potlucks; if you need more peanut-butter ideas try these banana and peanut butter chew sticks for variety.
Recipe Overview
- Prep time: 10 minutes
- Cook time (melting): 5–7 minutes
- Chill/time to set: 1 hour
- Total time: about 1 hour 20 minutes
- Servings: 12–16 squares (8×8 pan)
- Difficulty: Easy
- Method: Stovetop melting of butter and peanut butter, melt-in marshmallows, fold in cracker crumbs, press into pan and chill.
My Experience Making This Recipe
I tested this version several times to find the best butter-to-peanut-butter ratio for hold and flavor. Early batches were too soft at room temperature, so I increased the graham cracker crumb slightly and added a short chill step to firm the bars without making them rock-hard. The final version cuts cleanly with a sharp, warm knife.
How to Make Peanut Butter Marshmallow Squares
Start by lining an 8×8-inch baking pan with parchment, leaving an overhang at two sides for easy removal. Gently melt 1/2 cup (113 g) unsalted butter and 1 1/2 cups (about 400 g) creamy peanut butter in a medium saucepan over low heat, stirring constantly until smooth. Add 4 cups mini marshmallows (or one 10 oz bag) and stir until the marshmallows fully collapse and the mixture is glossy — this usually takes 2–3 minutes; avoid high heat to prevent scorching. Remove from heat and stir in 3 1/2 to 4 cups graham cracker crumbs (about 12–14 full crackers crushed) until evenly combined. Press the mixture into the prepared pan with a lightly buttered spatula or the back of a measuring cup, chill for at least 1 hour, then lift out and cut into squares. For a chocolate finish, melt 4 oz (115 g) semi-sweet chocolate and drizzle or spread on top once slightly cooled. For more texture ideas, I referenced techniques from classic recipes like classic peanut butter cookies while testing.
Expert Tips for Success
- Control heat: melt butter and peanut butter over low to medium-low heat; aggressive heat will scorch peanut butter and make marshmallows seize.
- Use mini marshmallows: they melt faster and more evenly than large ones — save time and ensure a smooth mix.
- Measure crumbs by volume, then adjust: start with 3 1/2 cups graham crumbs and add a little more if the mix seems too sticky; you want it pressable but not greasy.
- Press firmly but not overly compact: compacting too much can make the bars dense; press until flat and even for clean slices.
- Equipment: a silicone spatula and an 8×8-inch pan with parchment overhang make removal and cleanup simple.
How to Serve Peanut Butter Marshmallow Squares
- Cut into small 1.5-inch squares and serve on a platter for parties or school lunches. For dunking, pair with cold milk or a mocha coffee.
- Dress them up: top with a thin chocolate glaze or sprinkle flaky sea salt right after drizzling to create a salty-sweet contrast. You can also make holiday shapes similar to these Christmas peanut butter candies for festive presentations.
- Plate with fruit: sliced apples or banana rounds offer a fresh counterpoint and are great for kids’ snack trays.
Storage and Reheating Guide
Store finished squares in an airtight container at room temperature for up to 3 days. To extend life, refrigerate up to 10 days — bring to room temp 10–15 minutes before serving for softer texture. For longer storage, freeze separated by parchment in a single layer in a freezer-safe container for up to 3 months; thaw in the fridge overnight. Warm slightly in a 200°F (93°C) oven for 5–7 minutes wrapped in foil to renew a just-made texture, or microwave single pieces for 8–10 seconds if you prefer gooey.
Recipe Variations
- Gluten-free: use gluten-free graham cracker crumbs or swap in 4–5 cups puffed rice cereal (Rice Krispies) to keep it naturally gluten-free. I tested the cereal swap and it lightened the bars nicely.
- Dairy-free: replace butter with 1/2 cup refined coconut oil or a vegan buttery spread and use dairy-free chocolate for the drizzle.
- Chocolate-peanut twist: fold 1/2 cup mini chocolate chips into the warm mixture or spread 4 oz melted chocolate on top; for inspiration see this chocolate peanut butter valentines heart.
- Nut-free swap: use sunflower seed butter instead of peanut butter and increase salt slightly to balance; the technique remains the same.
Nutritional Highlights
- Key benefits: peanut butter provides plant-based protein and healthy fats, which help keep you satisfied.
- Calories and portioning: these are energy-dense treats — aim for small squares (12–16 per batch) as a sensible portion.
- Allergens: contains peanuts; may contain dairy and gluten unless you use substitutions listed above. Always label accordingly for guests.
Troubleshooting Common Issues
- Too sticky after chilling: warm gently in the microwave 8–12 seconds or let sit at room temp for 10–15 minutes before cutting. Avoid overheating or they’ll become oily.
- Bars too crumbly/fall apart: the mix needs more binder — melt a tablespoon or two more peanut butter into the warm mixture and press again, or add a touch more melted butter/oil.
- Marshmallows not fully melted or lumpy: keep heat low and stir continuously; covering the pan briefly off heat lets residual steam finish melting. If needed, return to very low heat and stir until smooth.
Frequently Asked Questions
Q: Can I use chunky peanut butter?
A: Yes. Chunky adds texture and crunch; you may need to press a bit firmer so the bars hold together. I recommend stirring a few extra crumbs in if pieces are large.
Q: Why did my bars get oily on top?
A: Overheating peanut butter can separate oils. Keep melt temp low, remove from heat as soon as the mix is smooth, and press firmly before chilling. If oil separates, blot with a paper towel and re-chill.
Q: Can I make these ahead for a party?
A: Absolutely. Make up to 3 days ahead refrigerated or freeze for up to 3 months. Thaw in the fridge overnight and bring to room temp before serving for best texture.
Q: Can I skip the crumbs and use cereal instead?
A: Yes — puffed rice cereal works well and keeps the bars lighter. Fold cereal in gently to avoid crushing it, and press with a paper towel to avoid compacting too much.
Conclusion
If you want a quick, no-bake treat that’s flexible and reliably tasty, these Peanut Butter Marshmallow Squares are a go-to. For another simple take on the same concept and printable steps, see this guide: Peanut Butter Marshmallow Squares (4 Ingredients!) – Gluesticks Blog.
Print
Peanut Butter Marshmallow Squares
- Total Time: 80 minutes
- Yield: 12-16 squares 1x
- Diet: Vegetarian
Description
A quick, nostalgic no-bake treat that combines sweet, salty, and chewy flavors, perfect for any occasion.
Ingredients
- 1/2 cup (113 g) unsalted butter
- 1 1/2 cups (about 400 g) creamy peanut butter
- 4 cups mini marshmallows
- 3 1/2 to 4 cups graham cracker crumbs
- 4 oz (115 g) semi-sweet chocolate (optional)
Instructions
- Line an 8×8-inch baking pan with parchment, leaving an overhang on two sides.
- Melt the unsalted butter and creamy peanut butter in a medium saucepan over low heat, stirring constantly until smooth.
- Add mini marshmallows and stir until fully melted and the mixture is glossy.
- Remove from heat and stir in the graham cracker crumbs until evenly combined.
- Press the mixture into the prepared pan with a spatula or measuring cup and chill for at least 1 hour.
- Lift out and cut into squares. If desired, melt the semi-sweet chocolate and drizzle or spread on top once slightly cooled.
Notes
For a gluten-free option, use gluten-free graham cracker crumbs or puffed rice cereal. For a dairy-free version, replace butter with coconut oil.
- Prep Time: 10 minutes
- Cook Time: 7 minutes
- Category: Dessert
- Method: Stovetop melting
- Cuisine: American
Nutrition
- Serving Size: 1 square
- Calories: 200
- Sugar: 15g
- Sodium: 100mg
- Fat: 10g
- Saturated Fat: 2g
- Unsaturated Fat: 8g
- Trans Fat: 0g
- Carbohydrates: 25g
- Fiber: 1g
- Protein: 4g
- Cholesterol: 10mg