Cook the green beans in simmering salted water for 4 minutes or until tender, then drain and cool.
Heat the grill. If using fresh sardines, brush with olive oil and grill for 5 minutes on each side. Allow to cool for 10 minutes. If using canned sardines, drain well.
Grill the pita bread for 1 minute, turning once, then cut into long wedges.
To assemble the platters, arrange the sardines and chilies on four dinner plates. Toss the green beans in olive oil, sea salt and pepper and arrange on plates. Crumble the feta over the top and scatter with pine nuts.
Top the pita bread with a dollop of taramasalata and an olive. Add the cucumber and a dollop of yogurt, scatter with red onion, olives, dried oregano and fresh oregano leaves. Drizzle with olive oil, add a lemon wedge and serve.