An herbal sorbet captures all the vibrant fragrance of the summer herb garden in a single spoonful. Imagine the intense citrus of lemon verbena, the soft perfume of lavender or the bracing pine of rosemary funneled into refreshing scoops of sweet-tart ice. I delight in finding ways to use herbs as the focus of a dish rather than as a seasoning, and herbal sorbets are the purest example of this. With little more than sugar, water and herb sprigs, these desserts are among the easiest to prepare.
You can call them sorbets, sherbets, granitas or ices, but they all are in the same family and share the same methods of preparation. If you learn to make one flavor, you can make many.
How to Make Herbal Ices
I use two basic methods to extract the herbal flavors. One uses a blender and the other a saucepan. Aside from an ice cream maker, which is not required for granitas, a fine-meshed strainer is the only special piece of equipment you’ll need. Be sure it has a very fine mesh so that it can hold back the small bits of herb leaf that may distract from a smooth texture.
1. For the blender method, measure the sugar, water and lemon juice into the blender container, add a generous quantity of herb leaves, and blend for a minute or so until smooth. Pour the liquid through the fine strainer and immediately freeze it in an ice cream maker. Although you can use ordinary granulated sugar, fine sugar (also known as baker’s sugar) is a better choice because it will dissolve faster in the syrup without heat. This method works best with lemon verbena, lemon geranium, tarragon and mint. It also works well with basil, but you’ll get the best color if you blanch the basil leaves first (a quick dip in boiling water followed by a cold-water bath).
2. The second method is called an infusion, and it truly is as easy as brewing tea. Bring sugar and water to a boil in a saucepan, toss in a bundle of herb sprigs (stems and all), cover the pan and take it off the heat. Let the herbs steep for 15 minutes or so and then strain. The syrup will carry the flavor and fragrance of the herb while the green vegetal flavor of the leaf, along with the stems, will stay behind. Next, add citrus juice and freeze. This is the more versatile method because it works with nearly any herb. The infused syrups also can be mixed with fruit purees like berry, melon or peach, creating endless combinations of herb and fruit sorbets.
The most important thing to keep in mind with these frozen desserts is that they must be balanced between sweet and tart. If you make a sorbet with nothing but sugar, water and an herb, it will taste cloying and flat, but add the correct amount of lemon juice and the flavor will be bright and refreshing. Fruit purees each have their own level of sweet and tart, so the proportion of sugar syrup may vary with each particular fruit.
The other important variable in a sorbet is the texture. Too much sugar will make a sorbet that is too soft; too little sugar will make a sorbet that is too icy. In my restaurant kitchen, we use a refractometer, a handheld instrument that measures brix, the sugar-to-water ratio. In your home kitchen, you’ll need to rely on your taste buds or a recipe. My standard formula is 1 cup of sugar to 3 ¼ cups water and ¼ cup lemon or lime juice.
You can scoop these sorbets into stemmed glasses to stand alone, or serve them on top of fresh fruit, floating in a chilled soup or even as a garnish for a cocktail. They are ideal endings for summer meals when something light and refreshing is called for, but they also work well as a first course or as part of a weekend brunch. Once you discover how effortless they are to prepare, you’ll find yourself churning up new flavors week after week.
Jerry Traunfeld, author of The Herbal Kitchen (William Morrow, 2005), received the James Beard Award for Best American Chef of the Northwest in 2000.