Making a good tomato sauce is an essential technique in any cook's repertoire, and there are many ways to layer the flavor. Tomato leaves can add a unique element to sauce as they have an intense, signature aroma that is similar to basil.

The test kitchen at Cook's Illustrated confirmed that a batch of sauce they made with tomato leaves wasn’t as sweet but did add a unique taste as compared to a plain batch of sauce. Since the alkaloids in the leaves are volatile, they recommend adding them to sauce during the last 10 minutes of cooking, and you can also remove them before serving.

If you want to experiment at home with your own tomato plant trimmings, try ¼ cup of chopped-up leaves for every 8 cups of sauce, and keep the leaves contained with cheesecloth so they don't disperse. Thoroughly wash the leaves, as you don't want dirt or leaf-hungry insects winding up in your food, and opt for leaves that haven't been sprayed with chemicals.