Trim the ends of the lemongrass stalks, peel off a couple of the tough outer layers, and chop the core. Use a good sharp heavy knife to slice cleanly through the core—it's usually still kind of tough.
Put the chopped lemongrass, lemon verbena, lemon balm, and lemon zest in a heatproof bowl—preferably one you can pour from easily. Pour 2 cups boiling water over the herbs and zest.
Let the herbs steep for about 20 minutes (the fragrance will be heavenly). Pour the liquid through a strainer into a pitcher or spouted measuring cup, then stir in the sugar—about a tablespoon, or more if you like.
Pour the liquid into 2 ice-filled glasses. Top each with about 1/2 cup black tea and put a
sprig of lemon verbena in each—its fragrance will add to the pleasure of your sipping.
I'm the food editor at Sunset magazine. Before Sunset, I was the executive editor at Saveur, and before that I worked at the late, lamented Gourmet. I edited The Sunset Cookbook (Oxmoor, 2010), was the main author of The One-Block Feast (Ten Speed Press, 2011), and edited Sunset's Edible Garden Cookbook (Oxmoor, 2012). I love cooking and never get tired of it—even though it's my job.