S’mores Soda Float Brownies

A decadent fusion dessert combining fudgy brownies, toasted marshmallows, and a creamy root beer float twist—perfect for indulging your sweet tooth with a nostalgic campfire flair.

Brownies have always brought back childhood memories for me, but the first time I made these S'mores Soda Float Brownies, my family was instantly hooked. The fun float twist surprised everyone and made them extra special.

Ingredients

• Brownie Layer: 1/2 cup (115 g) unsalted butter, melted, 1 cup (200 g) granulated sugar, 2 large eggs, 1 tsp vanilla extract, 1/3 cup (40 g) unsweetened cocoa powder, 1/2 cup (65 g) all-purpose flour, 1/4 tsp salt, 1/4 tsp baking powder
• Graham Cracker Base: 1 cup (100 g) graham cracker crumbs, 1/4 cup (60 g) unsalted butter, melted, 2 tbsp sugar
• Marshmallow & Float Topping: 1 1/2 cups (75 g) mini marshmallows, 1 cup (240 ml) vanilla ice cream, slightly softened, 1/2 cup (120 ml) root beer or cola, 2 oz (55 g) milk chocolate, chopped or chips

Instructions

Prep Pan:

Preheat oven to 350°F (175°C). Line an 8x8-inch (20x20 cm) baking pan with parchment paper, leaving an overhang for easy removal.

Make Base:

In a small bowl, combine graham cracker crumbs, melted butter, and sugar. Press evenly into the bottom of the prepared pan to form a crust.

Mix Brownie Batter:

In a medium bowl, mix melted butter and sugar. Whisk in eggs and vanilla until smooth.

Combine Dry Ingredients:

Sift in cocoa powder, flour, salt, and baking powder. Stir until just combined.

Assemble Layers:

Pour brownie batter over the graham cracker base and smooth the top.

Bake:

Bake for 28–32 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.

Add Marshmallows:

Remove pan from oven and immediately sprinkle mini marshmallows evenly over the brownies. Return to oven for 3–4 minutes, until marshmallows are puffed and golden.

Cool:

Remove brownies and cool completely in the pan.

Chocolate Drizzle:

Once cooled, drizzle melted chocolate over the marshmallow layer. Chill until set.

Serve with Float:

Just before serving, cut into squares. Top each brownie with a scoop of vanilla ice cream and pour over a splash of root beer or cola to create a float effect. Serve immediately.

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Whenever I bake this dessert, my kids take turns topping their brownies with ice cream and soda, giggling as the float bubbles up. It has become a favorite for movie nights at home.

Required Tools

To make these brownies, you need an 8x8-inch (20x20 cm) baking pan, mixing bowls, whisk, spatula, parchment paper, a small saucepan or microwave for melting chocolate, and an ice cream scoop for serving.

Allergen Information

This recipe contains wheat (gluten), eggs, milk, and soy (if using chocolate chips with soy lecithin). It may also contain traces of nuts depending on product labels.

Nutritional Information

Each serving has approximately 320 calories, 15 g total fat, 45 g carbohydrates, and 3 g protein.

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Enjoy this playful twist on a classic treat—serve right away for the best soda float experience, and watch everyone smile with every bite.

Recipe Guide

→ How do I achieve toasted marshmallows without burning?

After baking, sprinkle marshmallows and return pan for just 3–4 minutes; watch closely for golden puffs or use a kitchen torch for extra toastiness.

→ Can I substitute root beer with another soda?

Yes! Cola is a popular alternative. Any creamy soda works to provide the classic float effect, tailoring flavor to your preference.

→ Can I make these brownies ahead of time?

You can bake the brownies up to a day in advance and store chilled. Add ice cream and soda float topping just before serving for best texture.

→ What is the ideal pan size for baking?

An 8x8-inch (20x20 cm) pan is recommended to ensure thickness and even baking for these layered brownies.

→ Are there gluten-free options for the crust?

Replace regular graham crackers with gluten-free versions to make the base suitable for gluten intolerances.

→ How do I serve these for parties?

Cut squares ahead, lay on a platter, provide ice cream and soda separately for guests to build float-topped brownies on demand.