This 5-ingredient slow cooker flag day sweet is the kind of low-effort, high-reward dessert that fits right into a busy summer schedule. The star is a big handful of raw mini marshmallows tossed straight into the crock, then coaxed into a gooey, almost fudge-like bar with just four simple pantry additions. Think of it as a playful mash‑up of a s’mores bar and a patriotic potluck dessert: buttery graham crumbs, white chocolate, and bright pops of red and blue from dried berries. It’s an easy, hands-off treat that travels well, feeds a crowd, and has that nostalgic, campfire-adjacent flavor without ever turning on the oven.
Serve this slow cooker flag day sweet slightly warm or at room temperature, cut into rustic squares or scooped into small bowls. It pairs nicely with vanilla ice cream or lightly sweetened whipped cream, and a few fresh strawberries or blueberries on the side will echo the red-and-blue theme. A pot of coffee, iced tea, or lemonade balances the sweetness, and if you’re serving a larger spread, it fits nicely next to fruit salads, grilled foods, and other picnic-style dishes.
Slow Cooker Flag Day Marshmallow SweetServings: 8-10
Ingredients
4 cups raw mini marshmallows
1 1/2 cups graham cracker crumbs
1/2 cup unsalted butter, melted
1 cup white chocolate chips
3/4 cup dried mixed berries (such as dried strawberries, cherries, and blueberries)
Directions
Lightly coat the inside of a 4- to 6-quart slow cooker with nonstick cooking spray or a thin film of neutral oil to help prevent sticking.
Toss the raw mini marshmallows directly into the bottom of the slow cooker, spreading them into an even layer so they cover the base. This should visually resemble a fluffy white bed of marshmallows in a top-down view.
In a medium bowl, stir together the graham cracker crumbs and melted butter until the crumbs are evenly moistened and resemble damp sand.
Sprinkle the buttery graham mixture evenly over the marshmallow layer, covering as much of the surface as possible without pressing down too firmly.
Scatter the white chocolate chips evenly over the graham layer, then sprinkle the dried mixed berries over the top so you get red and blue pops of color throughout.
Cover the slow cooker with the lid and cook on LOW for 1 1/2 to 2 hours. The marshmallows should be melted and gooey around the edges and the white chocolate chips mostly softened, while the top still looks a bit textured rather than fully liquid.
Turn off the slow cooker and, with the lid slightly vented, let the dessert cool for about 20 to 30 minutes to set. The mixture will firm up as it cools, making it easier to slice or scoop.
Once set but still slightly warm, run a thin spatula around the edges to loosen. Cut into squares directly in the crock or scoop portions into small bowls. Serve warm or at room temperature.
Variations & Tips
For a stronger s’mores vibe, swap half of the white chocolate chips for semisweet or milk chocolate chips. To lean into the flag theme, focus your dried fruit on red and blue: use dried cherries or strawberries for the red and dried blueberries for the blue. You can also stir in a small handful of chopped toasted nuts (such as pecans or almonds) with the graham crumbs for extra crunch, keeping in mind any nut allergies among guests. If you prefer things less sweet, reduce the white chocolate chips to 3/4 cup and increase the graham crumbs slightly for more toasty flavor. For a richer base, use salted butter instead of unsalted and omit any extra added salt. Food safety tips: Keep the slow cooker on LOW only; avoid using HIGH for this recipe, as the sugar in the marshmallows and white chocolate can scorch quickly. Do not leave the slow cooker unattended for long stretches the first time you make this—check around the 1 1/4-hour mark to gauge how hot your particular appliance runs. Once cooked, cool the dessert to room temperature within 2 hours and store leftovers tightly covered in the refrigerator for up to 3 days. Reheat gently in short bursts in the microwave or on LOW in the slow cooker, and discard if you notice any off smells, mold, or separation.
