Preheat the oven to 400 degrees F. Butter four 6-ounce ramekins; sprinkle with sugar and tap out the excess. Put the ramekins on a baking sheet; transfer to the freezer while you make the batter.
Heat the chocolate syrup and 2 tablespoons butter in a small saucepan over low heat until the butter melts, about 2 minutes; let cool. Whisk the egg yolk in a medium bowl. Slowly whisk in the chocolate syrup mixture until combined.
Beat the egg whites with a mixer on medium speed until foamy. Add the cream of tartar and beat until soft peaks form, about 2 minutes. Add 1 tablespoon sugar and beat until stiff peaks just form, 1 to 2 more minutes.
Fold one-third of the beaten egg whites into the chocolate-yolk mixture until combined. Fold in the remaining egg whites in two additions until no white streaks remain.
Photograph by Kang Kim
Thank you! your flag was submitted.