In 4 large aluminum foil sheets, place the fish and the artichokes. In a small bowl, whisk the remaining 5 ingredients (olive oil through leeks) and drizzle over the fish and artichokes.
Place an additional large sheet of foil over the fish and seal the open edges tight.
Place the pouches on the grill and cook for 10 to 15 minutes, until fish flakes easily with a fork and vegetables are tender. Serve warm.