Edinson Cavani and Neymar scored either side of half-time as Unai Emery's men rocketed nine points clear at the top.
Mbappe - whistled throughout by the home fans - was in a forgiving mood, the teenager incredibly wasting four clear-cut chances before he inadvertently deflected in a late consolation for the hosts.
Cavani was less generous in the first half as he spared his team-mate's blushes by stabbing in the opener inside 20 minutes.
Mbappe's ongoing profligacy plagued PSG after the restart but it ultimately proved inconsequential to the result, which Neymar sealed by winning and scoring a penalty.
Monaco, who for much of the match looked incapable of mounting a fightback, did gain hope when Joao Moutinho's free-kick deflected off Mbappe to cut the deficit, but it was not enough to prevent the champions from falling further off the pace.
Mbappe was sprightly on his return to the principality, but his first chance came and went early on as he raced onto Neymar's pass and touched the ball past the onrushing Danijel Subasic, only to inexplicably finish wide of a vacant net from a manageable angle.
A second clear-cut chance for an early opener escaped PSG in similarly agonising fashion. Cavani cleverly helped Mbappe's byline cut-back to the far post, where a stretching Julian Draxler could only steer it the wrong side of the upright.
But the visitors only had to wait until the 19th minute to make their dominance count.
Adrien Rabiot fed a simple pass into Draxler's feet and the German did likewise for an unmarked Cavani, who poked high into the roof of the net at close range.
Monaco had Subasic preventing greater damage at the end of a one-sided first half after the goalkeeper reacted sharply to Draxler's low drive.
PSG started the second half in much the same manner as they began the first, Neymar first cracking the right-hand post before Mbappe tried to be too cute in a one-on-one.
But any frustration evaporated even quicker this time around as the Brazilian dispatched a 52nd-minute spot-kick into the bottom-left corner, having been bundled over in the area by Almamy Toure.
However, even the two-goal buffer could not ease Mbappe's nerves around goal. The France star blazed another fine chance over the bar and could have had four when he poked wide with a final one-on-one.
And the jitters seemed to spread, Cavani nodding wide of a gaping target shortly after Jemerson had turned a low cross against his own post.
Mbappe became even more central to Emery's irritation when Moutinho's free-kick flicked off his head and wrong-footed Alphonse Areola in the 81st minute, but PSG were never truly threatened again in stretching their lead at the top.
