For the Best Tomato Sauce, Add Leaves

If you’re cooking with tomatoes from your own garden, the fruit isn’t the only part of the plant worth harvesting.
By and

Published July 15, 2022.

When tomato season hits, I always have to make a batch of senior editor Steve Dunn’s fresh tomato sauce. This recipe results in a sauce that perfectly captures the sweet, savory, and aromatic flavors of peak-season fruit. What’s the secret? A lot of tomatoes, a bushel of science—and a surprising secret ingredient. 

Read on, or watch the latest episode of What’s Eating Dan?, for more on the delicious tomato alchemy behind this summery sauce.

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All About Aroma

When you cook tomato sauce from scratch, your kitchen smells absolutely incredible. That’s one of the best parts of cooking: But it’s also a problem, flavor-wise.

You build flavor in a sauce by driving off water and concentrating the fruit’s stable aroma compounds. But the fact that the sauce smells so good means that the unstable aromatic compounds in your food are no longer in the sauce—they have volatilized into the air. 

So the secret to the freshest tasting tomato sauce is to find a way to replace those volatile aromatic compounds—and not drive them off.There are a couple of different ways you can do this. First, as Steve’s recipe instructs, you can reserve some of the tomato gel, the most flavorful part of the tomato, and stir it in off-heat to help restore the fresh tomato taste. 

Then, if you want to take the flavor a step further, you can call upon an unconventional ingredient: Tomato leaves.

How to Cook with Tomato Leaves

Tomato leaves contain 2-isobutlythiazole, a compound responsible for the plant’s distinctive aroma. Commercial tomato products, like ketchup, often include an isolated form of that compound to boost fresh tomato flavor.

If you have a garden full of tomatoes, though, you’ve got a great source of 2-isobutlythiazole right in your backyard. Here’s how to use tomato leaves to boost your sauce’s flavor.

1. When you harvest your tomatoes, pluck a handful of leaves from the plant.

2. Toss the leaves into the sauce and steep them for 10 minutes.

3. Remove and discard the leaves. 

Taste your sauce, and you’ll find that the tomato flavor has been both heightened and made more complex and earthy.

To learn more about the science of cooking with tomatoes, watch the latest episode of What’s Eating Dan? below.

Fresh Tomato Sauce

Tomato flavor is fleeting—which is why we examined every part of the fruit and our cooking method until we'd engineered a sauce that was bright, sweet, and aromatic.
Get the Recipe

Griddled Tomato Sandwiches

Any tomato can star in a sandwich— if you know how to play to its strengths.
Get the Recipe

Roasted Tomatoes

Our roasting method concentrates the flavor of peak-season and supermarket tomatoes alike.
Get the Recipe


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