Marinated Cucumber, Onion, and Tomato Salad

This is that crunchy-tangy-sunny salad you want to eat straight out of the fridge with a fork. Thin, crisp cucumbers, sweet tomatoes, and peppery onions hang out in a punchy marinade and somehow turn into the most refreshing little side dish that goes with literally everything. It’s backyard barbecue energy, no grill required. Cheap, fast, fresh, and it tastes even better after a little fridge nap. I mean… what more do we ask from a bowl of vegetables?

My husband calls this “that jar salad” because he once caught me shaking it in a mason jar like a cocktail while trying to wrangle a toddler and a rogue dog. The kids pick out the tomato chunks first; he goes nose-first for the onion ribbons; I guard the cucumbers like a dragon. It’s become our default “oh shoot, we need a vegetable” move, but also the thing I bring to every potluck when I don’t have time, which is always. We’ve eaten it on the porch in August with grilled corn and, yes, in January in sweats because crunchy produce with a zippy marinade just makes life feel brighter.

Kitchen Talk

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I’ve made this with every kind of cucumber under the sun—English for fuss-free slicing, little Persian guys when I want extra crunch, and the big garden ones that need their seedy centers scooped. If the onion feels aggressive, I give the slices a quick cold-water bath while I mix the marinade and they chill right out. I’ve tried it with balsamic and… we’re still friends, but it turns the whole thing muddy. Red wine vinegar or apple cider vinegar keep it bright. Dill makes it classic, basil makes it dreamy, and mint is the unexpected “why is this so fresh?” moment. I once forgot the oil and it tasted like salad punishment; don’t be me—just a glug makes the acid behave. Also, if your tomatoes are a little meh, a pinch of sugar or honey is magic. Not dessert-y, just balanced.

Shopping Tips

– Vegetables: Look for firm cucumbers with smooth skin, tomatoes that feel heavy for their size, and a red onion that’s tight and shiny. Roma or cherry tomatoes keep shape best.
– Fresh Herbs: Dill, basil, or mint all work. Grab a bunch that smells like something—if you have to lean in and still can’t smell it, skip.
– Fats & Oils: A decent extra-virgin olive oil makes the marinade round and silky. If you only have neutral oil, mix in a splash of EVOO for flavor.
– Specialty Item: Red wine vinegar or apple cider vinegar gives bright, clean tang. Save balsamic for another day if you want to keep the colors vivid.
– Sweeteners: A little sugar or honey softens the bite. Honey adds floral notes; plain sugar disappears cleanly—use what you keep in the pantry.
– Budget Swaps: Go with Persian cucumbers when on sale, or grab Romas over heirlooms. Dried dill or Italian seasoning works in a pinch—just use a light hand.

Prep Ahead Ideas

– Slice cucumbers and onions earlier in the day; keep them in cold water in the fridge so they stay crisp. Drain before tossing.
– Mix the marinade in a jar and stash it separately. Shake before using so everything comes back together.
– If tomatoes are super juicy, cut them closer to serving or store them in a separate container to avoid watery vibes.
– In the morning: chop, jar the marinade, and tuck it all in the fridge. In the evening: drain, toss, herb it up, eat.

✔Time-Saving Tricks

– Use a mandoline or the “thin slice” side of your box grater for lightning-fast cucumber and onion ribbons.
– Cherry or grape tomatoes cut in half are speed demons—no dicing required.
– Don’t peel English or Persian cucumbers; the skins are tender and add extra crunch and color.
– Keep a “house dressing” jar in the fridge—vinegar, oil, salt, pepper, tiny sweetener—so you’re already halfway there.
– The only place not to rush: give it a little rest after tossing so the flavors can get cozy.

✔Common Mistakes

– Ending up with a watery bowl: been there. If your tomatoes are extra juicy, spoon off a little liquid or toss in a fresh splash of vinegar and another drizzle of oil to rebalance.
– Onion too fiery? Quick cold-water soak or a tiny pinch of salt and a squish of lemon tames the bite.
– Over-acidifying: if it’s too sharp, add a splash more oil and the smallest hint of sweetener until it stops yelling.
– Sad, mealy tomatoes: if they’re out of season, use cherry tomatoes—they’re consistently better.
– Over-salting early: salt wakes up veggies over time, so go light at first and adjust right before serving.

What to Serve It With

– Grilled anything: chicken thighs, steak bites, shrimp skewers.
– Crispy salmon, roasted chickpeas, or a big tray of falafel.
– Crusty bread and whipped feta for a snacky dinner.
– Couscous, quinoa, or buttered rice to catch all that tangy juice.

✔Tips & Mistakes

– Salt lightly, taste later—marinades get louder as they sit.
– Thin slices = quick marination; chunky pieces = more crunch. Choose your adventure.
– Add herbs at the end so they don’t go bruised and sad.
– If it feels flat, it probably needs a pinch of salt or a tiny sweet note, not more vinegar.
– Big bowl for tossing, small bowl for serving. Let the splash zone be private.

✔Storage Tips

Pop leftovers into a lidded container and chill. The veggies get more pickled and a touch softer—honestly amazing cold straight from the fridge. If a puddle forms, just stir, or drain a little and add a fresh glug of oil. Breakfast people, hear me out: pile it next to scrambled eggs or on avocado toast. It’s great for up to a few days, but the herbs are happiest added fresh each time.

✔Variations and Substitutions

– Dill classic, basil dreamy, mint zippy. Parsley is the sturdy friend that never wilts on you.
– Swap red wine vinegar for apple cider vinegar; rice vinegar makes it extra gentle.
– Honey ↔ sugar, both fine. Maple works too but use just a touch so it doesn’t taste like brunch.
– Add-ins that play nice: feta crumbles, olives, chickpeas, or torn mozzarella.
– Heat lovers: red pepper flakes or a sliced jalapeño.
– Avocado is glorious but add it right before serving so it doesn’t go mushy.
– If cucumbers are seedy, scoop the centers for extra crunch and less water.

Frequently Asked Questions

Marinated Cucumber, Onion, and Tomato Salad

Fresh cucumbers, juicy tomatoes, and crisp red onion soak in a tangy-sweet vinaigrette. A simple, chilled side that brightens any meal.

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Prep Time: 15 minutes minutes

Total Time: 15 minutes minutes

Servings: 6

Ingredients

 

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Main Ingredients

• ▢ 4 cup thinly sliced cucumbers
• ▢ 2.5 cup ripe tomatoes, cut into wedges
• ▢ 1 cup thinly sliced red onion about half a large onion
• ▢ 0.5 cup apple cider vinegar
• ▢ 0.25 cup water
• ▢ 2 tbsp extra-virgin olive oil
• ▢ 1.5 tbsp granulated sugar
• ▢ 1 tsp kosher salt
• ▢ 0.5 tsp freshly ground black pepper
• ▢ 1 tsp dried dill
• ▢ 1 tsp minced garlic
• ▢ 2 tbsp chopped fresh parsley for garnish

Instructions

Preparation Steps

• Whisk vinegar, water, sugar, olive oil, salt, pepper, dill, and garlic in a bowl until the sugar dissolves.
• Slice the cucumbers and red onion thinly. Cut the tomatoes into wedges.
• Combine cucumbers, tomatoes, and onion in a large mixing bowl.
• Pour the marinade over the vegetables. Toss to coat well.
• Cover and chill 20–30 minutes, tossing once. Taste, adjust seasoning, and garnish with parsley before serving.

Notes

Variation: Swap dill for dried oregano and add crumbled feta for a Greek-style twist. For more bite, use red wine vinegar instead of cider vinegar.

Storage tip: Refrigerate up to 2 days. For the crispest texture, add tomatoes right before serving.

This recipe is an original creation inspired by classic Marinated Cucumber, Onion, and Tomato Salad flavors. All ingredient ratios and instructions are independently developed.