Step 1

Place the cucumbers in a large colander and toss with a couple of large pinches of salt. Set the colander in a large bowl or in the sink and let the cucumbers stand 30 minutes at room temperature to release some of their water. Meanwhile, whisk the sour cream, vinegar, oil, mustard, a pinch of salt, and a few grinds of pepper together in a large bowl; set aside.

Step 2

Gently pat the cucumbers dry with a paper towel. Add the cucumbers, red onion, and dill to the dressing and toss gently to combine. Taste and season with salt and pepper as needed.