If you need a side dish that’s crisp, refreshing, and full of flavor, Marinated Cucumber Tomato Onion Salad is the perfect choice. It’s made with simple vegetables—juicy tomatoes, crunchy cucumbers, and thin-sliced red onion—then tossed in a tangy, herby marinade that gets better as it sits. The result is a bright, chilled salad that pairs with almost anything: grilled chicken, fish, burgers, rice bowls, sandwiches, or a big summer BBQ spread.
This is one of those recipes you’ll come back to all year. In warm months, it feels light and cooling. In colder months, it adds a fresh bite next to rich meals. It’s also budget-friendly, quick to prepare, and naturally gluten-free. Best of all, you don’t need fancy ingredients—just good produce, vinegar, olive oil, and a few seasonings.
Why You’ll Love This Salad
This salad is all about balance. Tomatoes add sweetness and juiciness, cucumbers bring crunch, and onions add a sharp bite. The marinade pulls everything together with acidity, salt, and herbs, turning everyday vegetables into a side dish that tastes like it came from a restaurant. As it rests, the flavors deepen, the onions mellow, and the tomatoes release their juices—creating a lightly dressed salad that’s perfect for scooping with bread or serving over greens.
Ingredients You’ll Need
- 2 large cucumbers, sliced (English cucumbers work great)
- 3 to 4 ripe tomatoes, sliced or cut into wedges
- 1 medium red onion, thinly sliced into rings
- 1/4 cup extra virgin olive oil
- 1/4 cup red wine vinegar (or apple cider vinegar)
- 1 tablespoon lemon juice (optional but bright)
- 1 to 2 teaspoons sugar or honey (optional, to balance acidity)
- 1 teaspoon dried oregano (or Italian seasoning)
- 1/2 teaspoon garlic powder (or 1 clove fresh garlic, minced)
- 1 teaspoon salt (adjust to taste)
- 1/2 teaspoon black pepper
- 2 tablespoons chopped fresh parsley (optional)
- Optional add-ins: feta cheese, olives, avocado, chickpeas
How to Make Marinated Cucumber Tomato Onion Salad
1) Slice the vegetables
Start by washing and drying your produce. Slice cucumbers into rounds or half-moons. Cut tomatoes into thick slices or wedges so they hold their shape. Thinly slice red onion into rings. If you prefer a milder onion flavor, soak the onion slices in cold water for 10 minutes, then drain well.
Place all vegetables into a large bowl.
2) Mix the marinade
In a small bowl or jar, whisk together olive oil, vinegar, lemon juice (if using), sugar or honey (if using), oregano, garlic powder, salt, and black pepper. Taste the marinade and adjust: add more vinegar for extra tang, more salt for bolder flavor, or a touch more sweetener if the tomatoes are not very ripe.
3) Toss and chill
Pour the marinade over the vegetables and toss gently to coat. Cover and refrigerate for at least 20–30 minutes, though 1–2 hours is even better. The longer it chills, the more flavorful it becomes.
Right before serving, toss again and sprinkle with fresh parsley if you like.
Tips for the Best Flavor and Texture
- Use ripe tomatoes: The better the tomatoes, the better the salad. If your tomatoes are bland, add a little extra salt and a squeeze of lemon.
- Don’t slice too thin: Thicker tomato slices stay firm and look better on the plate.
- Chill for best results: This salad tastes best cold after the flavors have time to blend.
- Drain if needed: Tomatoes release juice as they sit. You can serve it as-is (many people love the extra marinade) or drain slightly for a cleaner presentation.
- Season in layers: A pinch of salt on the tomatoes before adding the marinade helps bring out their natural sweetness.
Easy Variations
This salad is simple, but it’s also flexible. Here are a few ways to switch it up:
Greek-inspired version
Add feta cheese, kalamata olives, and a pinch of oregano. Swap red wine vinegar for lemon juice and add a little extra olive oil.
Spicy version
Add red pepper flakes or thin-sliced jalapeño for heat. A little spice makes the tomatoes taste even sweeter.
Creamy version
Add a spoon of Greek yogurt to the marinade for a creamy dressing. This turns the salad into something closer to a cucumber-tomato slaw.
Protein boost
Stir in chickpeas or white beans. It becomes a light lunch that’s filling but still fresh.
Herb-forward version
Use fresh dill, basil, or mint. Basil pairs especially well with tomatoes, while dill gives a cool, classic flavor.
What to Serve With Cucumber Tomato Onion Salad
This marinated salad works with almost any meal. Serve it with:
- grilled chicken, steak, or fish
- burgers, kebabs, or sausages
- rice bowls, quinoa, or couscous
- sandwiches and wraps
- roasted potatoes or baked sweet potatoes
It’s also great on a mezze-style plate with hummus, pita, olives, and cheese.
Storage and Make-Ahead Tips
This salad is great for meal prep, but it’s best within the first day for maximum crunch.
- Refrigerator: Store in an airtight container for up to 2 days.
- Best texture: Eat within 24 hours. After that, cucumbers soften and tomatoes release more juice.
- Make ahead: You can slice the vegetables and mix the marinade separately, then combine 30 minutes before serving for the freshest result.
Frequently Asked Questions
Can I use cherry tomatoes instead of sliced tomatoes?
Yes. Halve them so they absorb the marinade better.
What vinegar is best?
Red wine vinegar gives classic flavor, but apple cider vinegar is slightly sweeter and also works well.
How do I make the onions less strong?
Soak sliced onions in cold water for 10 minutes, or use sweet onion instead of red onion.
Marinated Cucumber Tomato Onion Salad is one of the easiest ways to add color, crunch, and brightness to your table. Once you make it once, you’ll start keeping the ingredients on hand because it goes with everything and takes almost no time to prepare.