No Bake Brownies with Marshmallows and Graham Crackers

No Bake Brownies are the answer when it’s too warm to turn on the oven, but you still want something chocolatey and sweet. This recipe comes together with just eight simple ingredients, about 20 minutes of hands-on time, and a two-hour chill in the fridge. No oven means your kitchen stays cool, and you still end up with a fudgy, marshmallow-studded treat that tastes like a cross between a brownie and a s’more.

These are also one of the easiest recipes to hand off to kids, since almost every step is just stirring and pressing into a pan. The only part that needs an adult is melting the chocolate chips and evaporated milk together on the stove. Once that’s done, the rest comes together in minutes, and the hardest part is waiting for them to set.

Quick Facts

• Prep Time: 20 minutes
• Chill Time: 2 hours
• Total Time: 2 hours 20 minutes
• Yield: 3 dozen
• Method: No-Bake (stovetop only, no oven)
• Ingredient Count: 8
• Best For: Warm weather, kid-friendly, s’mores flavor fans

What Each Ingredient Does

• Graham Cracker Crumbs: Form the base and give the brownies their structure, plus that faint honey-toasted flavor that leans into the s’mores taste.
• Powdered Sugar: Sweetens the crumb mixture and helps bind everything together into a dense, fudgy texture instead of a crumbly one.
• Walnuts: Add crunch and a little nutty depth against all the soft, chewy texture. Leave them out if you want a smoother bite or have a nut allergy in the house.
• Miniature Marshmallows: Melt slightly into the mixture and give the brownies pockets of gooey sweetness. This is the ingredient that pushes the flavor toward s’mores territory.
• Chocolate Chips: The main chocolate flavor and what holds the whole mixture together once melted with the evaporated milk.
• Evaporated Milk: Melts the chocolate chips into a smooth, pourable mixture and adds richness without thinning things out the way regular milk would.
• Salt: Balances the sweetness so the brownies don’t taste flat or one-note.
• Vanilla: Rounds out the chocolate flavor and adds warmth to the overall taste.

Tips for Success

• Crush the graham crackers as fine as possible. Use a rolling pin over a gallon zip-top bag, or a food processor if you have one. Larger chunks mean a crumblier bar that doesn’t hold together as well.
• Grease the pan with butter, not cooking spray. Butter gives a cleaner release and adds a little extra flavor along the edges. Parchment paper works too, and makes lifting the whole batch out for cutting even easier.
• Don’t skip the full 2-hour chill. These brownies need that time in the fridge to firm up. Cutting in early is the number one reason people end up with brownies that fall apart instead of holding a clean square.
• Use a warm, dry knife for cutting. Run your knife under hot water and dry it off between cuts. This keeps the chocolate layer from dragging or sticking as you slice.
• Stir the chocolate mixture constantly over low heat. Evaporated milk and chocolate can scorch fast if the heat’s too high or you walk away. Low and steady is the way to get a smooth, glossy mixture.

Variations and Substitutes

• Marshmallow Fluff instead of miniature marshmallows: Swap in about 1 cup of fluff. It’ll make the mixture a little softer and stickier, but it still sets up fine in the fridge.
• Peanut butter chips instead of half the chocolate chips: Swap in 1/2 cup peanut butter chips for a chocolate peanut butter version. Melt them together with the remaining chocolate chips and evaporated milk the same way.
• Leave out the nuts: Skip the walnuts entirely for a smoother texture, or swap in a different nut like pecans or almonds if you want the crunch with a different flavor.
• Add a sprinkle of flaky sea salt on top: Not a substitution, just an easy way to dress these up for a more grown-up flavor if you’re serving them beyond the kids’ table.

Storage Tips

Counter storage: Once the brownies have fully set from their initial 2-hour chill, they can be stored at room temperature in an airtight container for up to 3-4 days.

Refrigerator storage: For longer freshness, keep them in the fridge in an airtight container for up to 1-2 weeks. Chilled brownies will have a firmer, denser bite.

Freezer storage: Wrap individual squares in plastic wrap, then store in a freezer-safe bag or container for up to 3 months. Thaw in the fridge overnight or at room temperature for about an hour before serving.

Keep them airtight no matter where you store them. Graham cracker crumbs and marshmallows both pick up moisture and odors easily, so a loose cover on the counter or in the fridge will dry out the edges fast.

Layer with parchment or wax paper if stacking. This keeps the squares from sticking together, especially once they’ve softened a bit at room temperature.

Frequently Asked Questions

Can I make these ahead of time for a party? Yes, these are a great make-ahead treat. They actually need the chill time anyway, so make them the day before, and they’ll be ready to cut and serve.

Can I double the recipe? Yes, just use a 9×13-inch pan instead of an 8×8. The chill time stays about the same, but check that the mixture has set all the way through the middle before cutting.

Why did my brownies turn out crumbly instead of fudgy? This usually means the crumb mixture and chocolate mixture weren’t fully combined, or the graham cracker crumbs were too coarse. Make sure the crumbs are finely crushed and stir until everything is evenly coated in the chocolate mixture.

Are these gluten-free? Not as written, since regular graham crackers contain wheat. Swapping in gluten-free graham crackers should work fine, though the texture may vary slightly by brand.

How many people does this recipe serve? This recipe makes sixteen brownies. Cut the squares smaller for a bigger yield if you’re serving a large group.

Can kids help make these from start to finish? Kids can handle almost every step, including crushing the graham crackers and stirring the crumb mixture. The only part that needs adult supervision is melting the chocolate chips and evaporated milk on the stove.

What to Serve with No Bake Brownies

Since these are a warm-weather, no-oven treat, they pair best with other easy, cool-friendly foods that fit the same laid-back vibe.

• A cold, fruity drink: This Old-Fashioned Sherbet Punch is an easy match; both are perfect for the same warm-weather gatherings these brownies are made for. For something simpler, this Fresh Squeezed Lemonade is a refreshing, tart contrast to the rich chocolate.
• A scoop of vanilla ice cream: Serve a brownie à la mode with this No Churn Custard Ice Cream, which needs no ice cream maker and no oven, keeping the whole dessert spread heat-free.
• Iced coffee for an after-dinner pairing: A homemade iced coffee cuts through the sweetness and marshmallow richness, and it’s just as heat-free to make as the brownies themselves.
• A savory main and side if you’re serving these at a get-together: These brownies close out a casual dinner like Slow Cooker Shredded Pork Tacos well, since the slow cooker keeps the kitchen just as cool as skipping the oven for dessert does. 

Other Recipes You Might Enjoy

If you are looking for no-bake treats, you may like my Corn Flake Cookies or my 3-Ingredient Mint Truffles. You might also like these Lemon Oatmeal No Bake Cookies. For a baked brownie, try Cakey Brownies or Matcha Brownies.