Drake Cameos in Lil Dicky's 'Dave' with Brad Pitt

Drake made a cherry-on-top cameo for the season finale of Lil Dicky's "Dave" series -- an episode that also boasted Brad Pitt and Rachel McAdams appearances!!!

As fate would have it, Drake's actually a superfan of the show -- which just wrapped its third season -- and he said exactly that to Dicky, in person.

Dicky says, "Drake is like the top of the mountain top musically and as a rapper," and when they met ... Drake told him "the show is one of the more important shows of our generation."

High praise, for sure, and Dicky told The Hollywood Reporter scoring Drake, Rachel and Brad created a major challenge for his team -- "With all of them, my writers' room was like, 'This is kind of crazy that you’re putting all your eggs in these baskets because what if they say no?' These people don’t even do TV. Drake hasn’t done TV since 'Degrassi."

But he move forward confidently, saying ... "Honestly, I think the show can have a tendency to get overlooked. Once you sit down and watch, it’s kind of objectively a great show. These are like the biggest stars of our time validating our show."