This 4-ingredient oven baked marshmallow dessert is the kind of easy, nostalgic sweet you make when you want maximum excitement with very little effort. Whole white marshmallows melt and puff in the oven, creating a gooey topping over a buttery pantry-style base, and the result lands somewhere between a cobbler, a crisp, and a campfire-inspired dessert casserole. It is especially handy for family gatherings, sleepovers, and casual Sunday dinners when you need a crowd-pleasing treat made from simple ingredients already in the cupboard.
Serve this dessert warm with a scoop of vanilla ice cream or a spoonful of lightly whipped cream to balance the sweetness. Fresh strawberries, raspberries, or sliced bananas make a nice contrast, and for drinks, coffee, cold milk, or hot cocoa all pair beautifully. If you are putting it out for a family dessert table, small bowls and dessert spoons are ideal since the marshmallow topping stays deliciously soft and stretchy while warm.
4-Ingredient Oven Baked Marshmallow Dessert
Servings: 8
Ingredients
4 cups raw whole white marshmallows
1 cup graham cracker crumbs
1/2 cup unsalted butter, melted
1/2 cup sweetened condensed milk
Directions
1. Preheat the oven to 350°F and lightly butter or grease an oven-safe cast iron roasting pan or similarly sized baking dish.
2. In a medium bowl, stir together the graham cracker crumbs and melted butter until the crumbs are evenly moistened.
3. Press the crumb mixture evenly into the bottom of the prepared pan to form a simple crust.
4. Drizzle the sweetened condensed milk evenly over the crumb base.
5. Scatter the whole white marshmallows all over the top in an even layer, covering the surface generously.
6. Bake for 12 to 15 minutes, until the marshmallows are puffed and lightly golden on top.
7. Let the dessert cool for 5 to 10 minutes so the topping settles slightly, then scoop and serve warm.
Variations & Tips
Chocolate chip version: Sprinkle 1/2 cup semisweet chocolate chips over the crumb base before adding the marshmallows for a more candy-bar-like flavor. This creates little pockets of melted chocolate that pair especially well with the toasted marshmallow top.
Fruit variation: Add a thin layer of sliced bananas or strawberries between the condensed milk and marshmallows for a softer, slightly fresher finish. Keep the fruit layer light so the dessert still bakes evenly and does not become watery.
Extra crunch tip: For a firmer base, bake the graham cracker crust by itself for 5 minutes before adding the condensed milk and marshmallows. That brief pre-bake helps the crust hold together better when scooped.
Browning tip: Watch closely during the last few minutes of baking because marshmallows can go from pale to deeply browned rather quickly. If you want a lighter finish, pull the pan as soon as they puff and turn just a little golden.
Make-ahead note: This dessert is best served shortly after baking while the marshmallows are still soft and gooey. If you have leftovers, rewarm individual portions in short bursts so the topping loosens again before serving.