Even Perfect Tomatoes Can Use a Little Cream of Tartar

This ingredient hidden at the back of your spice cabinet helps tomatoes strike the perfect balance of sweetness and acidity.

Published July 26, 2022.

Congratulations! You waited patiently all year, searched high and low at the farmer’s market, and have finally found the most coveted treat of high summer: A fresh-from-the vine, perfectly ripe tomato. 

When you take such a specimen home, there are a few universally-acknowledged guidelines you must follow. Your perfect tomato should be enjoyed promptly. It should be consumed fresh, not cooked. It should not be stored in the refrigerator (though we’re a little skeptical about that one). And when it comes to actually eating it, simpler is always better—think thick, drippy slices sandwiched between two soft slices of mayo-slicked white bread.

I’m all for this ultra-minimalist approach. But one tiny, quick step will bring that simple sandwich to the next level: Seasoning your tomato slices with cream of tartar.

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Cream of Tartar on a Tomato?

That’s right: That powder you use to make chocolate soufflés and lemon meringue pie is also your secret tomato seasoning weapon. 

Here’s why: Tomatoes taste their best when they strike a balance between sweetness and acidity. Cream of tartar is an acidic ingredient that has the power to boost brightness without contributing extra liquid or distinct flavors, that way vinegars or lemon juice would (this is also the secret to attaining the lemoniest lemon bars). 

Round Out The Flavor Profile

And while you’re at it, why not round out your seasoning sprinkle with a few more flavor-balancing components? While showering a perfect tomato with a strongly-flavored herb or spice would be tomato season sacrilege, a light, simple seasoning snaps a tomato’s taste into the perfect balance of  juicy, sweet, tart, meaty, and savory flavors. 

My colleague Lan Lam uses an ideal combination in her recipe for griddled tomato sandwiches

  • Cream of tartar
  • Sugar, for a touch of sweetness
  • Black pepper, for subtle warmth
  • Salt, to help you taste it all

With this seasoning mix in your back pocket, your perfect tomatoes will be even better—and your less-than-perfect ones can be elevated too.

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