Glenn Murray bagged his sixth goal in as many games to break the deadlock for Palace before Bolasie took centre stage to send Sunderland slumping to another emphatic home defeat following the setback against Aston Villa by the same scoreline last month.
Bolasie had scored just once in the league this season prior to his treble on Saturday, but ruthlessly put Sunderland to the sword as Dick Advocaat's side were emphatically brought back to earth after beating local rivals Newcastle United last weekend.
Connor Wickham did pull one back in the 90th minute for the hosts, but it was a scant consolation.
The result leaves Advocaat's men still hovering just three points above the drop zone, while Palace are pushing for a top-10 finish.
The return to fitness of Jack Rodwell had handed Sunderland a pre-match boost, with Palace also given a given lift as they welcomed back a key figure in the form of skipper Mile Jedinak, who had missed the previous four games through suspension.
Roared on by a vociferous crowd, Sunderland made most of the early running, but were a touch fortunate not to be reduced to 10 men after 15 minutes, Rodwell escaping with a yellow card following a reckless challenge on midfield counterpart James McArthur.
And from the resulting free-kick, home skipper Lee Cattermole came close to gifting the visitors the opening goal as his attempted clearance flew just wide of the post.
Having weathered the early storm, Palace began to assert themselves, with the pace and movement of Wilfried Zaha, Bolasie and Jason Puncheon keeping a nervy-looking Sunderland defence on its toes.
The best Sunderland could muster before the break was an acrobatic volley from Steven Fletcher that forced goalkeeper Julian Speroni into a regulation save.
The game exploded into life at the start of the second half, however, as the visitors unleashed a quickfire, four-goal barrage.
Murray got things going when he nodded home a superb Bolasie cross at the back post after 48 minutes and the in-form striker then returned the favour almost immediately, providing a headed assist for the DR Congo winger to make it 2-0.
Sunderland were still all at sea three minutes later when Bolasie beat John O'Shea to Jedinak's throughball before calmly lobbing the advancing Costel Pantilimon.
That goal prompted a number of home fans to head for the exits and that became a mass exodus when Bolasie claimed his third and Palace's fourth after 62 minutes, with Murray again creating the opening.
Wickham did provide a last-minute reply for the visitors, but it was too little, too late for Advocaat's men, who need to regroup quickly ahead of next weekend's crunch trip to Stoke City.
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