Make ahead: The dressing can be made up to 4 days ahead, placed in an airtight container, and refrigerated. The beans can be steamed one day ahead and kept in a zip-top baggie in the refrigerator. Toss with the pecans, onions, and cheese the day you plan to serve the salad.

Tips:
– Use fresh green beans. They should be firm, bright green, and snap easily (see Quick Tip above).
– Don’t overcook the beans. Steam just until crisp-tender, then plunge into ice water to stop the cooking.
– Choose the right mint. Spearmint is ideal here; it’s milder and sweeter than peppermint.
– Toast the nuts. Don’t skip this step – it deepens their flavor.
– Use good-quality feta. Look for block feta, preferably in brine, for the best texture and taste.
– Soften the raw onion’s bite, if needed. If your red onion is too strong for your taste, soak the chopped pieces in cold water for 10 to 15 minutes, then drain and pat dry.
– Let the dressing rest. Mix it up at least 30 minutes ahead to let the flavors meld before tossing with the salad.