Making a Meringue for Baked Alaska
In a double boiler over simmering water, beat egg whites and cream of tartar with a portable mixer on low speed for 1 minute.
Continue beating on low speed until meringue reaches 160°, about 12 minutes. Remove from the heat; add vanilla. Beat on high speed until stiff peaks form.
Quickly spread over ice cream, sealing meringue to cake layer.