Method:
Cook orange juice to reduce by half; allow to cool.
In a large saucepan, bring stock, 1 tablespoon olive oil and a pinch of salt to simmer. Add quinoa and simmer for 15 minutes. Fluff quinoa and place in a large mixing bowl to cool. Add bell peppers, leeks, red onion, chives and mint to quinoa. Season to taste. In a separate bowl, whisk together reduced orange juice and 3 tablespoons olive oil. Set aside.
Season sablefish pieces. Place a small amount of olive oil in a non-reactive saute pan. Place pan over high flame and heat to the smoking point. Gently place fillet pieces, skin side down in pan. Cook on skin side to crispy golden brown. Turn once, and complete cooking on the other side. Toss mizuna with some dressing and place on a large platter (or 4 individual plates). Place quinoa salad on top. Gently place sablefish fillets on top. Drizzle with remaining dressing.