Marinated Cucumbers, Onions, and Tomatoes

This is my go-to marinated cucumbers onions and tomatoes recipe, and it never lets me down.

This is the kind of side dish that shows up at every summer cookout and church potluck, and for good reason. Cucumbers, onions, and tomatoes marinate together in a simple vinegar dressing, and the longer they sit, the better they genuinely taste.

My grandmother made a version of this every summer when the garden was overflowing with cucumbers and tomatoes, and it’s stayed one of my most reliable no-cook sides ever since.

Why You’ll Love This Recipe

A few reasons this side earns its classic status.

Genuinely refreshing: bright, tangy, and light.
No cooking required: just slice and marinate.
Great for meal prep: improves as it sits.
Simple ingredients: nothing exotic required.

Why This Works

Salting the sliced cucumbers and letting them sit for about 15 minutes before combining with the other vegetables is what draws out excess water, keeping the final dish from turning watery and diluting the dressing. Skipping this step leaves you with a marinade that gets progressively thinner as the cucumbers release their liquid over time.

Step-by-Step

Slice the cucumbers thin and toss them with a pinch of salt in a colander set over the sink. Let them sit for about 15 minutes, this draws out excess water.

Pat the cucumbers dry, then combine them with sliced onion and halved cherry tomatoes in a large bowl.

Whisk together white vinegar, a bit of sugar, olive oil, and a pinch of salt and pepper for the marinade. Pour over the vegetables and toss to combine.

 

Refrigerate for at least 30 minutes, though a few hours or overnight is even better. Toss again before serving, garnished with fresh dill if you have it.

Tips

• Salt the cucumbers first, this keeps the final dish from turning watery.
• Let the vegetables marinate for at least 30 minutes, longer is genuinely better.
• Use a mandoline for uniformly thin cucumber slices.
• Toss again right before serving, the dressing settles at the bottom.
• This dish genuinely tastes best the day after it’s made.

Variations

• Add crumbled feta cheese.
• Use apple cider vinegar instead of white vinegar.
• Add fresh dill or basil.
• Swap sugar for honey.

What to Serve With

• Grilled chicken or burgers.
• A simple sandwich.
• Crusty bread.
• Iced tea.

Storage

Refrigerator: store in an airtight container for up to 5 days.

Freezer: not recommended, the fresh vegetables don’t hold up frozen.

Reheating: this dish is meant to be served cold, no reheating necessary.

Make Ahead

This dish is genuinely built for making ahead, the flavor deepens the longer it sits in the fridge.

Frequently Asked Questions

How long should I marinate this?

At least 30 minutes, though overnight in the fridge gives the best flavor.

Why did my dish turn watery?

The cucumbers likely weren’t salted and drained first, this step is essential for keeping the dressing from getting diluted.

Can I make this a day ahead?

Yes, and it’s recommended, this dish genuinely tastes better the longer it sits.

Final Thoughts

This dish proves a simple summer classic never really goes out of style. Give it a try for your next cookout or potluck.