Homemade Swiss meringue instead of marshmallows:
4 large egg whites (do not use egg whites from a carton)
¾ cup cane sugar
¼ teaspoon cream of tartar
½ teaspoon pure vanilla extract
Pinch sea salt
1. Make the meringue by combining the egg whites with the sugar in a heat-proof mixing bowl over a saucepan of simmering water. Place over medium heat and whisk constantly for 2 minutes. Continue to whisk every couple of seconds for another 2-3 minutes, until mixture is warm and sugar has dissolved. If you want to take the temperature of the mixture, you’re looking for about 145 degrees F.
2. Carefully pour the egg white/sugar mixture into the bowl of a stand mixer along with the cream of tartar, vanilla, and salt. Using the whisk attachment, beat on low speed and gradually increase the speed to high until stiff peaks form, about 5-6 minutes. The meringue should look like thick shaving cream. This can be done a day in advance and stored in a sealed container in the refrigerator.
For a chocolate no-churn ice cream version: add ½ cup cocoa or cacao powder to the mixture when whisking together.