Tuna potato salad is a delicious combination of tender baby potatoes, tuna, green beans, capers, and red onion. A lemony Dijon dressing adds loads of flavor and this protein packed salad is perfect for lunch or dinner.
Cut potatoes in half and in a large pot, cover them with salted water and bring to a boil over high heat. Cook until just tender, about 8 minutes.
Add the green beans to the water during the last minute of cooking time. Drain in a colander and allow to cool somewhat.
In small bowl, whisk the salad dressing ingredients together until combined. (Or use a small jar with a lid to shake them together like I do).
Put the potatoes and beans in a large serving bowl and add the capers, tuna, red onion. Pour the dressing over and gently toss to combine. Garnish with parsley.
Notes
Potatoes. This salad works best with waxy, new potatoes. You can also use Yukon god potatoes cut into uniform pieces. Avoid starchy potatoes like russets.
Salted water. Add a generous pinch of salt to the cooking water for the best flavor.
Beans. The quick cooking time here means the green beans stay bright green without the need for an ice bath. If you use frozen green beans, there will be no need to cook them . They should, however, be defrosted, so you can plunge them into the potato water before draining.
Tuna. Drain the tuna completely, and break it up into chunks.
Don't overcook. We don't want mushy potatoes, so cook them until they are just fork tender, and drain them right away.
Dressing. Toss the lemon Dijon dressing with the potatoes while they are still warm. They will absorb maximum flavor.
Chill. You can serve this potato salad warm, but it's extra delicious after chilling in the fridge for a couple of hours to let the flavors meld.
Storage. Store leftover tuna potato salad in an airtight container in the fridge and use within 3-4 days.