Most green bean salads turn into a sad, waterlogged pile because the beans get boiled to death. This string bean and potato salad sidesteps that by dropping the beans in with the potatoes for the last five minutes only, they come out bright and snappy, not limp. The potatoes are fully tender by then, so you drain once and dress everything warm.
That warm potato soaks up the lemon-and-vinegar dressing while the raw onion and scallions stay crunchy, keeping every forkful balanced instead of mushy or flat.
Why boil potatoes and beans together?
Starting the potatoes first gives them a head start, they take longer to cook through. Dropping the string beans in the last five minutes means both finish at the same time. The potatoes turn fork-tender while the beans stay bright green and snappy.
No need for a second pot or timing two separate boils. You can test a potato and a bean together, pull the pot when both are right.
That crisp-tender bean texture is exactly what this salad needs against the soft potato chunks.
What does the lemon and vinegar dressing do?
Potatoes and beans are mild, earthy vegetables. They need an acid punch to wake them up.
Lemon zest brings a fragrant citrus note that the juice alone can’t. The apple cider vinegar adds a mellow tang, not sharp or sour.
Together they cut through the starchiness of the potatoes and brighten the green beans. The olive oil carries the flavors and coats each piece lightly.
The result is a salad that tastes fresh and balanced, not heavy or flat.
Why use raw onion and scallions here?
Cooking the onions would soften them and mute their sharpness. For this salad, you want that raw bite, a crunch that contrasts the tender potatoes and beans. Thinly sliced red onion adds a punchy, almost spicy kick.
Chopped scallions bring a milder onion flavor plus green flecks that make the dish look lively. Both stay crisp and distinct, never wilting into the background.
They keep each forkful interesting, with pops of texture and heat against the cool dressing.
Prep: 10 min · Cook: 30 min · Total: 40 min · Servings: 16 · Calories: 140 kcal
What to look for when buying and prepping
baby potatoes: Use waxy or all-purpose varieties; they hold shape after boiling. Halve them for even cooking.
string beans: Pick bright, thin beans that snap when bent; no limp or rusty spots. Trim just the stem end.
red onion: Slice paper-thin so the raw bite doesn’t overwhelm. A mandoline helps, but a sharp knife works.
lemon: Zest before juicing; the oils in the zest add a citrus punch that juice alone can’t match.
scallions: Use both white and green parts. Chop them finely so they distribute evenly through the salad.
How to make string bean and potato salad, step by step
Boil the potatoes
Halve 12 cups baby potatoes and put them in a large pot. Cover with cold water, bring to a boil. Cook until a fork slides in with slight resistance, about 25 minutes.
Don’t let them get mushy.
Add the string beans
With 5 minutes left on the potatoes, dump in 8 cups string beans. Stir once. After 5 minutes, fish out a bean and a potato.
The bean should be bright green and snap when bitten; the potato tender all through.
Drain and cool slightly
Drain the pot in a colander. Shake off excess water. Let them sit for 2 to 3 minutes so they stop steaming, you don’t want hot veggies wilting the onions later.
Make the dressing
In a small bowl, whisk 1/4 cup olive oil, 2 tablespoons apple cider vinegar, juice and zest of 1 lemon, 2 teaspoons kosher salt, and a few grinds of pepper. Taste, it should be tangy and bright.
Prep the aromatics
Thinly slice 1/2 red onion into half-moons. Chop 4 scallions, whites and greens.
Set aside. The onion should be paper-thin so it doesn’t overpower each bite.
Combine and dress
In a large bowl, toss the warm potatoes and beans with the red onion and scallions. Pour dressing over the top. Fold gently with a rubber spatula until every piece is coated.
Taste and add more salt if needed.
String Bean and Potato Salad
Ingredients
- 12 cups baby potatoes halved
- 8 cups string beans
- 1/2 red onion thinly sliced
- 1 lemon zested and juiced
- 1/4 cup olive oil
- 2 tablespoons apple cider vinegar
- 2 teaspoons kosher salt
- fresh cracked pepper
- 4 scallions
Instructions
Boil potatoes:
Cut the potatoes in half. Place them in a large pot and cover with water. Bring to a boil and cook until just fork-tender.Add string beans:
During the last 5 minutes of boiling, add the string beans to the pot. Cook until tender yet crisp. Drain both potatoes and beans.Whisk dressing:
In a small bowl, whisk together the lemon zest, lemon juice, olive oil, apple cider vinegar, cracked pepper, and salt.Slice onion and scallions:
Thinly slice the red onion and chop the scallions.Toss salad with dressing:
In a large mixing bowl, combine the cooked potatoes, string beans, red onion, and scallions. Pour the dressing over the mixture and toss gently to coat. Adjust seasoning with additional salt if needed.
Storage and Serving
This salad is best served within a few hours of making, while the potatoes are still firm and the beans have a crisp snap. If you’re making it ahead, refrigerate it in a sealed container for up to 3 days. The texture will shift: potatoes soften and beans lose some crunch, but the flavor holds well.
Serve cold or at room temperature; let it sit out for 15 minutes if straight from the fridge. Stir gently before serving to redistribute the dressing. Do not freeze the assembled salad: the potatoes and beans turn mealy and waterlogged on thawing.
For leftovers, store in the fridge and eat within 3 days for the best texture.
What you can swap in this salad and what to leave alone
apple cider vinegar: white wine vinegar or extra lemon juice. White wine vinegar keeps the same acidity level; lemon juice adds more citrus punch, which works with the lemon zest. Start with 2 tablespoons of either, taste, and adjust.
The dressing will be slightly sharper with lemon juice.
red onion: shallot or sweet onion. Shallots give a milder, sweeter bite, slice them thin. Sweet onion (like Vidalia) is less punchy, so you might want a bit more.
Both still give that raw crunch the salad needs.
olive oil: avocado oil or grapeseed oil. This is a straight one-for-one swap.
The dressing will be less fruity but still coat the vegetables. Use a neutral oil if you prefer the lemon and vinegar to lead.
baby potatoes and string beans: Do not swap these. They are the heart of the dish. Substituting changes the texture and cooking timing entirely.
A different potato may fall apart; another bean may not soften in the same window. Keep them as written.
Tips
- If your potatoes are larger than bite-size, cut them into uniform 1-inch pieces so they cook evenly; uneven pieces lead to some mushy and some underdone.
- Taste a bean and potato together after dressing: if the salad tastes flat, add another pinch of salt and a squeeze of lemon juice to brighten it.
I still set a timer the moment the potatoes hit the boil, because the first time I guessed, I ended up with mash.
Frequently Asked Questions
Can I make this salad ahead of time?
Yes, you can. Store it in a sealed container in the fridge for up to 3 days. The texture does shift, the potatoes soften more and the beans lose some snap, but the flavor stays bright.
Let it sit at room temperature for 15 minutes before serving, then stir gently to redistribute the dressing.
How do I prevent the potatoes from getting mushy?
Boil them only until a fork slides in with slight resistance, about 25 minutes. Overcooking is the main cause of mushiness. Also, draining and letting them cool for 2 to 3 minutes stops carryover cooking.
Should I serve this salad warm or cold?
Either works, but it’s best within a few hours of making while the potatoes are still firm and the beans crisp. If you refrigerate it, serve cold or let it come to room temperature for 15 minutes. The dressing clings better when the vegetables are slightly warm, so if serving cold, stir well before serving.
What’s the difference between string beans and green beans in this recipe?
None, they’re the same vegetable. The recipe calls them string beans, but you can use any fresh green bean. Look for bright, thin ones that snap when bent; avoid limp or rusty pods.
Trim just the stem end.
