Sandwiches - Pan-Grilled Salmon with Scallion Mayo

Serves 4 as main course
6 scallions
4 t olive oil
1 lb salmon fillet (abt 1 1/2 " thick), skinned and bones removed
1/4 cup mayo
1/3 cup finely chopped celery
2 t fresh lemon juice
1 1/2 t chopped fresh mint leaves
4 1/2" thick slices good-quality whole wheat bread
2 cups bite-size pieces frisee or mesclun (1 oz)

Heat grill pan over mod high heat until hot but not smoking. Meanwhile, toss scallions with 2 t oil and season with s & p. Pat salmon dry and coat with remaining 2 t oil and season with s & p. Cook scallions in grill pan, turning occasionally until soft and slightly charred, abt 6 mins, then transfer to cutting board to cool. Add salmon to grill pan and cook, turning over once, until just cooked through about 12 mins. Transfer with metal spatula to plate and cool slightly. Gently flake.
While salmon is grilling, finely chop scallions and stir into mayo with celery, lemon juice, mint. Season with s & p.
Toast bread and spread lightly w scallion mayo. Divide salmon among toasts, top with dollops of scallion mayo and pieces of frisee.