Why Some People Add Tomato Leaves To Their Homemade Red Sauce

Tomato sauce, how do we love thee? Let us count the ways. We love you as a simple, garlicky marina, we love you as a spicy arrabbiata, and we love you as a creamy alla vodka. Whether simmered with lots of butter or shot through with tender ground meat, tomato sauce is one of those kitchen essentials we just wouldn't want to be without, bringing sweetness, acidity, and depth of flavor to our pizzas, pasta, and more.

And as anyone who loves red sauce knows, the variations mentioned above are just a few of the ways this stellar condiment can be prepared. Every cook seems to have their personal preference for bringing out the flavor of the tomatoes, from adding a dash of Worcestershire sauce, fish sauce, or liquid aminos for extra umami oomph to stirring in some tomato paste for the extra body (via Southern Living). One tomato sauce flavoring you might not have heard of? Simmering in some tomato leaves right along with the fruit the plants bore.

How do you like to flavor your tomato sauce? With the classic aromatics of onion and garlic, or perhaps plenty of bright fresh basil? Maybe with a bit of bacon or guanciale, in the style of an alla gricia. But have you ever thought about throwing some tomato leaves into your sauce? According to Cook's Illustrated, doing so is a great way to bring earthy, herbal notes to your sauce. As any tomato gardener knows, the leaves boast an intense, peppery aroma, thanks to a compound, the outlet explains, called 2-isobutlythiazole. 

Commercial tomato products such as ketchup often add an isolated form of this compound to bring a depth of flavor, but if you're growing tomatoes in your garden or patio, you've got a natural source right there. Cook's Illustrated recommends rinsing a handful of tomato leaves and throwing them into your sauce in the last 10 minutes of cooking since the compound's flavor and aroma dissipate quickly. If you find you love the earthy flavor imparted by the leaves, you can go all-in and use them to prepare a spicy pesto, Riverford Organic Farmers notes.