America's Test Kitchen LogoCook's Country LogoCook's Illustrated Logo
Recipe Spotlight

Oil-Roast Your Tomatoes

And preserve the fleeting sweetness of tomato season.

Published July 31, 2023.

If you’ve never roasted tomatoes, you should: It’s a largely hands-off technique that yields bright, ultraconcentrated fruit that can perk up just about any dish, from pasta and crostini to salads and sandwiches. It’s a great method for preserving the flavor of peak-season tomatoes and coaxing out the flavors of blander supermarket fruits as well. 

Plus, roasted tomatoes can be frozen, so you can keep experiencing the taste of summer long after you’ve made them.

The only problem? Most recipes call for roasting the tomatoes for hours, and who wants that on a hot summer day? And even then, the results can vary from wet and pulpy to dried out and leathery.

Luckily, my colleague Lan Lam developed a technique that consistently results in bright-tasting, soft-but-intact tomato slices. Her secret? Roasting the tomatoes in a lot of olive oil.

Sign up for the Cook's Insider newsletter

The latest recipes, tips, and tricks, plus behind-the-scenes stories from the Cook's Illustrated team.

A Better Way to Roast Tomatoes

While many roasted tomato recipes call for drizzling tomato slices in a couple tablespoons of oil, a more liberal amount amps up flavor and keeps the tomatoes tender. Most importantly, it helps the slices to cook faster since oil is more efficient than air at transferring heat. 

When Lan roasted tomato slices that were merely drizzled with olive oil, the tomato took just under 4 hours to caramelize. But when she increased the amount of oil to ¾ of a cup (the most she could add to a rimmed baking sheet without risking that oil would spill over the sides), she was able to shave about an hour and a half off that cooking time. 

Two more  time-saving tricks: Lan slices the tomatoes in into ¾-inch-thick rounds—a shape that maximized their surface area for efficient evaporation and allowed her to fit 3 pounds in a single layer on the baking sheet. She also starts the tomatoes in an extra-hot, 425 degree oven, a blast of heat that helps the slices drive off their moisture faster.  Then, she turns the oven down to 300 degrees for the rest of the cook time to prevent the tomatoes from burning as they continue to concentrate.

One more smart move that helped ensure the most flavorful results: Lan chose large round field tomatoes for this recipe, which boast a higher ratio of the umami-rich “jelly” to skin than do the denser plum variety.

Here’s an overview of Lan’s simple method. For the full recipe, click here.

How to Roast Tomatoes

1. Heat oven to 425 degrees. Arrange tomatoes, sliced ¾ inch thick, in an even layer on a rimmed baking sheet lined with aluminum foil.

2. Drizzle olive oil evenly over the tomatoes, and place a couple of smashed garlic cloves on the sheet. Sprinkle the tomatoes with dried herbs.

3. Bake for 30 minutes, then remove the sheet from the oven and reduce the oven temperature to 300 degrees. 

4. Flip the tomatoes with a thin spatula, then return them to the oven until they’re spotty brown and collapsed, 1-2 hours. 


Roasted Tomatoes

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

How to Store Roasted Tomatoes

Transfer tomatoes and their oil to an airtight container and refrigerate for up to 5 days. Or, freeze them for up to 2 months.

Ways to Use Roasted Tomatoes

There are countless applications for these savory-sweet specimens. Here are a few of our favorites.

Top: Sandwiches, crostini, pizza, or polenta

Mix into: Scrambled eggs, frittata, quiche, pasta, deli salads, bread dough

And don’t forget to use the flavorful roasting oil! Try whisking it into salad dressing; drizzling it over meat, fish, vegetables, or pasta; or using it as a dip for crusty bread.


This is a members' feature.