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Got tomatoes? This refreshing tomato cucumber salad brings out the beauty of ripe tomatoes in a way you’ll want to eat again and again.

Cucumber Tomato Onion Salad
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What’s better than the sweet, juicy taste of a ripe tomato? We get giddy the moment they start to appear in their crimson, golden, and neon green splendor. Fresh tomatoes are at their best in simple preparations.

This tomato cucumber salad with red onion is just that: pure ingredients that when marinaded bring together the richest of flavors. This salad is perfect as a side dish for meals on the patio or summer barbecues: it goes with anything and everything. And the flavor is like pure gold.

Love tomato salads? Try Fresh Tomato Salad, Cucumber, Tomato & Avocado Salad, and Tomato, Basil & Mozzarella Salad.

Using best quality, ripe tomatoes

For the very best tomato cucumber salad, promise us one thing. Only make this salad with ripe tomatoes! Do not try to make this in the off-season, when grocery store tomatoes are pink and mealy. As with all simple preparations, the flavor of this salad depends on the quality of its ingredients.

  • Farmers market tomatoes or garden grown are best. We recommend buying your tomatoes at a farmers market if you have access to one, or growing them yourself.
  • Store bought can work, too. Try to find the best looking heirloom tomatoes you can buy at your local grocery store. Hydroponic greenhouse tomatoes tend to have better flavors.
  • Find multi-colored for a vibrant look. Multi-colored tomatoes work well here: the more the colors, the more vibrant the salad!
Cucumber tomato onion salad

How to make tomato cucumber salad

Combine juicy tomatoes with cool cucumber and zesty onion, and this tomato cucumber salad is like plant-based take on a Greek salad, without the standard feta cheese! Here’s how to make this it (or jump to the recipe below):

  • Soak the onion: Thinly slice the onion and let it soak for a few minutes in cold water. This helps to remove the strong bite of the onion.
  • Cut the veggies: Meanwhile, cut the cucumber into half-moons and the tomato into wedges. Finely chop the herbs.
  • Marinade: Combine all the veggies and herbs with olive oil, red wine vinegar and kosher salt. Allow it to marinade for at least 30 minutes, then serve.

Is marinading required?

Alex and I are always looking for shortcuts. This cucumber tomato onion salad calls for marinading for 30 minutes. Is it really necessary? Actually, yes! Here’s why:

  • The time lets the flavors meld and develop. We tasted this salad before and after the marinading time, and you’ll notice a difference. Marinading makes the flavors more developed than when the salad is freshly mixed together. Let it do its magic while you’re getting together the rest of the meal!
  • Make ahead tip: If you’d like, you can make this salad up to 2 hours in advance and store it covered at room temperature until serving. We recommend to not refrigerate this salad: it dulls the flavors.

Step it up with heirloom tomatoes

What are heirloom tomatoes? Heirloom tomatoes are tomato varieties that have been passed down through generations by saving the seeds. When you buy heirloom tomatoes, you’ll notice that their color and shape are much more varied than the typical round red tomato. They can vary from chartreuse to gold to purple to orange, and from small to medium to large.

Do you have to use heirloom tomatoes in this recipe? Not at all. We just love the look that heirloom tomatoes give, with all their vibrant colors. They also typically have a variety and nuance in flavor that makes the overall salad more intriguing. But you can use any ripe tomato that you like.

Cucumber tomato onion salad

How to serve it

How would you serve this cucumber tomato onion salad? We can think of so many summery recipes to accessorize with this salad; it’s perfect for a summer party, barbecue, or cookout on the deck. Here’s a few things we might serve with it:

Dietary notes

This cucumber tomato onion salad recipe is vegetarian, gluten-free, vegan, plant-based, and dairy-free.

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Tomato Cucumber Salad

Cucumber Tomato Onion Salad
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Got fresh summer tomatoes? This cucumber tomato onion salad brings out the beauty of ripe tomatoes in a way you’ll want to eat again and again.

  • Author: Sonja Overhiser
  • Prep Time: 10 minutes
  • Cook Time: 0 minutes
  • Total Time: 10 minutes
  • Yield: 4 1x
  • Category: Salad
  • Method: Raw
  • Cuisine: Italian

Ingredients

Scale
  • 4 to 6 large ripe tomatoes, multicolored if desired
  • 1 large cucumber (we like English cucumbers)
  • 1 medium red onion
  • 1 tablespoon minced fresh herbs (such as basil, thyme, oregano)
  • 2 tablespoons extra-virgin olive oil
  • 2 tablespoons red wine vinegar
  • ½ teaspoon kosher salt

Instructions

  1. Slice the onion into half moons and soak in water for 10 minutes to reduce the bite.
  2. Meanwhile, slice cucumbers into half circles. Slice tomatoes into wedges, leaving the seeds intact. Finely chop the herbs.
  3. Combine all ingredients in a bowl and stir gently to combine. Cover and rest for 30 minutes (or up to 2 hours) before serving.

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About the authors

Alex & Sonja

Hi! We’re Alex & Sonja Overhiser, authors of the acclaimed cookbooks A Couple Cooks and Pretty Simple Cooking—and a real life couple who cooks together. We founded the A Couple Cooks website in 2010 to share seasonal recipes and the joy of home cooking. Now, we’ve got over 3,000 well-tested recipes, including Mediterranean diet, vegan, vegetarian, pescatarian, smoothies, cocktails, and more!

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1 Comment

  1. Sunny25 says:

    Thank you for this recipe!! Someone brought this to a picnic once and it was so delicious, I couldn’t stop eating it. I always wondered how they made it, and now I know! Your recipe looks exactly like what I had, so I hope it’s the same. Can’t wait to try it!