Wash and lightly dry arugula. Place in a large bowl and set aside
Remove the tops from the radishes and cut in half. Set the flat half on a cutting board and cut into thin half moon slices. Add to arugula
Trim the ends from the scallions and dice through part of the greens. Place in the bowl with the radishes.
Add the quinoa, sunflower seeds and feta
In a jar with a tight fitting lid, combine the ingredients for the dressing and shake vigorously. Pour over the salad and toss until everything is well coated