Summer is my favorite time to talk about tomatoes.
Tomatoes are finally at their peak. They’re vibrant, juicy, and practically spilling out of every basket at the farmers market.
This is when they taste the best and are bright, fresh, and full of flavor.
Whether you’ve picked up a bunch of tomatoes from your favorite roadside stand or grabbed a few Roma tomatoes at the grocery store, now’s the time to put them to work.
Roma tomatoes are one of my favorites. They’re firm, meaty, and low on seeds, making them the best choice for everything from pico de gallo to tomato sauce.
And when summer hits, I find myself dicing up batch after batch for salads, taco bowls, pastas, and anything that could use a little juicy tomato flavor.
Today, I’m showing you the best way to dice Roma tomatoes. No culinary school required.
Whether you’re prepping a single tomato or a lot of tomatoes, these tips will help you get clean, even small cubes every time.
First Things First: Choose the Right Knife
For clean cuts through fresh tomatoes, you’ll want a very sharp knife. A serrated knife (like a bread knife) or a paring knife can work well, but the best knife for this job is one that can handle the tomato skin without squishing the juicy flesh underneath.
You want to avoid using a dull knife, which will just crush the tomato and send tomato juice and seeds flying. Trust me, the right knife makes all the difference.
Step 1: Prep Your Workspace
Start with a clean cutting board and wash your Roma tomatoes. Pat them dry with a paper towel.
If you’re working with a lot of tomatoes, give yourself space to work. You don’t want them rolling around.
Step 2: Remove the Core
Place the tomato stem end facing up. Use the tip of a paring knife in a circular motion around the top of the tomato to remove the tomato core. Roma tomatoes don’t always have a tough core, but it’s good to check.
Step 3: Cut the Tomato in Half
Now flip the tomato so the bottom of the tomato sits flat on the board. Slice it lengthwise down the middle to create two symmetrical halves.
Step 4: Scoop or Shake Out the Seeds (Optional)
If your recipe calls for less moisture (like salsa or pico de gallo), scoop out the tomato seeds with a spoon or gently squeeze them out.
This keeps your final dish from getting watery. If you’re making tomato sauce, you can leave the seeds in for extra flavor.
Step 5: Slice Vertically, Then Horizontally
Place the cut side of the tomato down on your board for stability. Using your sharp knife, make vertical slices about 1/4 inch apart (or thinner for a small dice). Then turn the tomato 90 degrees and make a series of slices in the opposite direction to form tomato cubes.
If you’re working with larger tomatoes, you may want to make one or two horizontal cuts across the width before you dice. For smaller tomatoes, you can skip that step.
Tips for Consistent Dicing
- Use a very sharp knife for the cleanest cuts
- Keep the entire tomato stable on the board by placing the cut side down
- Slice evenly. Thinner slices = more consistent tomato pieces
- For smaller pieces, increase the number of vertical and horizontal cuts
What If I’m Using Grape Tomatoes?
While today’s post focuses on Roma tomatoes, the method works similarly for grape tomatoes or smaller tomatoes. The main difference is you may want to cut them into quarters or halves instead of dicing, unless you’re going for an ultra-fine dice.
Can I Use a Food Processor?
If you’ve got a lot of tomatoes to prep and aren’t worried about presentation, a food processor can help. Just pulse carefully so you don’t end up with mush. It’s not the best choice for precise cuts, but great if you’re going straight into tomato sauce.
Storing Diced Tomatoes
Once you’ve finished dicing, transfer your tomato pieces to an airtight container and store in the fridge. They’ll keep for a few days and are ready to go for salads, sauces, or sandwiches.
Whether you’re cooking for one or meal-prepping a week’s worth of recipes, knowing how to dice Roma tomatoes properly can save time and make your dishes look and taste better.
It might take a little practice, but once you nail it, you’ll never go back to uneven chunks again!
