To make the meringue, add the egg white to a bowl. Add two tsp of the lemon sugar and a pinch of cornstarch to the egg and whisk well. A hand held electric whisk works best. Stop as soon as the egg whites are glossy and stiff peaks are achieved. Don't overwhip, or the egg whites will actually separate.
I prefer using whole milk for this drink, but other versions of milk should work just fine.
Use the lemon sugar on buttered toast, in tea, or in baking.