Homemade Marshmallow Cream

In a double boiler oven medium heat, heat the egg whites, sugar, and cream of tartar until it reaches 160ºF. Whisk mixture constantly during heating.

Transfer egg white mixture to bowl of a stand mixture fitted with a whisk attachment. Start the mixer at a slow speed and gradually increase the speed. Add in the vanilla and mix until mixture doubles in size. When thoroughly mixture and aerated, the mixture should be able to form stiff peaks and look glossy, white, and opaque.

Store in an airtight container overnight or use immediately (preferred).