public async Task <Session> GetSession(int sessionId) { var fetchAllSessions = _httpHelper.FetchSessions(); var sessionDetails = _httpHelper.FetchSession(sessionId); await Task.WhenAll(fetchAllSessions, sessionDetails); var session = fetchAllSessions.Result.SingleOrDefault(s => s.Id == sessionId); if (session == null) { throw new SessionNotFoundError(); } session.Description = sessionDetails.Result.Result; return(session); }