- For the marshmallow fluff:
- 3 egg whites
- 2/3 cup plus 2 tablespoons granulated sugar
- 3/4 cup light corn syrup
- 1/3 cup water
- 1 teaspoon vanilla
- For the whoopie pies:
- 1 box Betty Crocker® SuperMoist® milk chocolate cake mix
- 3/4 cup water
- 1/2 cup vegetable oil
- 3 eggs
- 1 box (4-serving size) chocolate instant pudding mix
- 1 container Hershey’s® s’mores frosting
- To make the marshmallow fluff: In the bowl of a stand mixer, beat egg whites at medium speed until light and frothy. Add 2 tablespoons sugar and beat until soft peaks form.
- Meanwhile, combine corn syrup, water and remaining sugar in a medium saucepan over medium heat. Bring to a boil. Heat mixture to 240°F, stirring occasionally (use a candy thermometer to read temperature). Remove from heat.
- With stand mixer on low speed, slowly add syrup mixture to egg white mixture. Increase to high speed and beat 7 minutes. Add vanilla and beat another 2 minutes, or until fluffy. Transfer to a clean bowl and set aside to cool.
- To make the whoopie pies: Heat oven to 350°F. Line two baking sheets with parchment paper or silicone baking mats.
- In the bowl of a stand mixer, combine cake mix, water, oil, eggs and pudding mix; stir on low speed until just combined. Increase to high speed and beat 1 minute.
- Use a 1 1/2-inch cookie scoop to scoop batter into 30 circles on baking sheets, about 1 to 2 inches apart. Bake until set, about 10 minutes (do not overbake). Cool 2 minutes on baking sheets, then transfer carefully to a cooling rack to cool completely.
- Pipe frosting on the flat side of one cookie; pipe marshmallow fluff on the flat side of the second cookie. Sandwich together and dip one edge in graham cracker crumbs.