Step 1: Preheat your oven to 350°F (175°C). Line a 9x13 inch baking pan with parchment paper, leaving an overhang on the sides to easily lift the brownies out later. Lightly grease the parchment.
Step 2: In a medium bowl, combine 1½ cups finely crushed graham cracker crumbs, ¼ cup granulated sugar, and ½ teaspoon ground cinnamon (optional). Pour in ½ cup melted unsalted butter and mix well until the crumbs are evenly moistened.
Step 3: Press the graham cracker mixture firmly and evenly into the bottom of the prepared baking pan. Bake for 8-10 minutes, or until lightly golden and fragrant. Remove from oven and set aside to cool slightly while you prepare the brownie batter.
Step 4: In a large, microwave-safe bowl or a double boiler, melt 1 cup (2 sticks) unsalted butter with 1 cup semisweet chocolate chips. Stir until smooth. Alternatively, you can use 4 ounces of unsweetened chocolate and 4 ounces of semisweet chocolate for a deeper flavor.
Step 5: Remove from heat and stir in 1¾ cups granulated sugar and ¼ cup packed light brown sugar. Whisk vigorously for about 1-2 minutes until the mixture is glossy and slightly thickened. This helps create that crinkly top!
Step 6: Beat in 4 large eggs, one at a time, mixing well after each addition. Stir in 2 teaspoons vanilla extract. The richer the vanilla, the better your smores brownies vanilla bean marshmallow recipe will taste.
Step 7: In a separate bowl, whisk together 1 cup all-purpose flour, ¾ cup Dutch-processed cocoa powder, ½ teaspoon baking powder, and ½ teaspoon salt. Gradually add the dry ingredients to the wet ingredients, mixing on low speed or by hand until just combined. Be careful not to overmix, as this can lead to tough brownies. Fold in an additional 1 cup of semisweet chocolate chips.
Step 8: Pour the brownie batter evenly over the pre-baked graham cracker crust. Return the pan to the oven and bake for 25-30 minutes, or until a toothpick inserted into the center comes out with moist crumbs attached (not wet batter). Do not overbake! Allow the brownies to cool completely in the pan on a wire rack before proceeding. For an extra rich treat, serve these brownies warm with a scoop of vanilla bean ice cream before adding the marshmallow layer. If you're looking for another indulgent dessert, consider making Decadent Chocolate Ganache Pumpkin Pie: A Seasonal Dream Come True.
Step 9: While the brownies cool, prepare the vanilla bean marshmallow. In a stand mixer fitted with the whisk attachment, add 2 large egg whites.
Step 10: In a small saucepan, combine ½ cup water, 1½ cups granulated sugar, ½ cup light corn syrup, and ¼ teaspoon salt. Cook over medium-high heat, stirring until the sugar dissolves. Continue to cook without stirring until the syrup reaches 240°F (116°C) on a candy thermometer (soft ball stage).
Step 11: As the syrup approaches 230°F (110°C), start beating the egg whites on medium-high speed until soft peaks form. Once the syrup reaches 240°F, carefully and slowly pour the hot syrup in a thin stream down the side of the mixing bowl into the whipping egg whites, making sure to avoid the whisk. Continue beating on high speed until the marshmallow is very thick, glossy, and holds stiff peaks (about 7-10 minutes). Beat in 1 tablespoon vanilla bean paste (or seeds from 1 vanilla bean) during the last minute of whipping.
Step 12: Once the brownies are completely cool, spread the vanilla bean marshmallow topping evenly over the cooled brownie layer.
Step 13: Set your oven broiler to high. Place the pan under the broiler for 1-3 minutes, watching constantly, until the marshmallow topping is beautifully golden brown and toasted in spots. This step is crucial for achieving that authentic s'mores flavor for your smores brownies vanilla bean marshmallow recipe. Immediately remove from the oven.
Step 14: Let the smores brownies vanilla bean marshmallow recipe cool slightly before slicing. For cleaner cuts, chill the brownies for at least 30 minutes. Use a sharp, warm knife. You can store any leftover brownies in an airtight container at room temperature for up to 3 days. For convenient storage, I often use Basics Glass Food Storage containers to keep them fresh. Why not try another classic like The Ultimate Giant Chocolate Chip Cookie Cake Recipe for your next gathering?