Now playing with pace and purpose, the Reds peppered Lynch's goal with attempts but Januzaj, Thorpe and Will Keane were all off target. So it was no surprise when Januzaj supplied a wicked inswinging free-kick from the right that was nodded past the exposed Lynch by Thorpe for a third goal.
Will Keane then made way, with just over an hour gone, and Lawrence was harshly booked for simulation after going down in the box before substitute Donald Love volleyed over the bar after more clever approach work had the Bolton defence at full stretch.
Last term's Under-21 champions camped in the Trotters' half for the remainder of the match and sub Jack Barmby forced a save out of Lynch and just failed to meet a driven cross by Love before clearing off his own line. Seconds later, Lingard won the ball inside the opposition half and went alone, drilling in a low drive for his second of the night.
There was still time for 16-year-old Cameron Borthwick-Jackson to make his debut at this level as a late replacement for Lawrence with United doubling the points tally for the season to six points from three games.
United: Amos; Varela (Barmby 70), Thorpe, M.Keane, Blackett; Januzaj, Cole, Ekangamene, Lingard, Lawrence (Borthwick-Jackson 86); W.Keane (Love 61). Subs not used: Sutherland, McConnell.