"I hope that comment about Valium doesn't set the tone for 2017 in this committee," said Sen. Sherrod Brown (D-OH).
As for the actual hearing, it followed the script of other Trump nominations, as Democrats accused Mnuchin of not answering ethics matters, zeroing in on his use of financial accounts located in Anguilla and the Cayman Islands.
In his hearing, Mnuchin strongly defended himself against charges from Democrats that he was the "foreclosure King" when he bought and helped operate the subprime mortgage lender IndyMac.
"I have been maligned as taking advantage of others' hardship in order to make a buck," Mnuchin said.
"Nothing could be further from the truth."
Meanwhile, the Senate's top Democrat was threatening again to slow walk votes in the full Senate on Trump Cabinet nominations, as he accused the GOP of rushing work to obscure ethics questions.
"These issues and others deserve to be thoroughly and rigorously reviewed by the Senate," said Sen. Charles Schumer (D-NY), who brought along his own props to a news conference to drive his point home.
Mr. Trump's spokesman and soon-to-be White House Press Secretary Sean Spicer blasted the moves of Schumer, telling reporters at a briefing that Democrats were using "stall tactics."
"There is really no excuse for the delay tactics and frankly, the partisanship," Spicer said at a briefing.
Schumer said Democrats might agree to allow quick votes on Mr. Trump's choices for Defense Secretary and Homeland Security Secretary.
Usually, the Senate convenes a few hours after an Inaugural Address, and confirms a series of nominees for a new President.
Back in 2009, the Senate okayed seven different nominees of President Obama on that first afternoon.
Even with all the partisan sniping, there was still room thankfully for a small bit of levity at one hearing, as a verbal miscue by former Texas Gov. Rick Perry sent everyone into gales of laughter, after Sen. Al Franken (D-MN) asked Perry if he enjoyed their meeting.
"I hope you are as much fun on that dais as you were on your couch," Perry said.
After more than a few chuckles, Perry tried to right the ship.
"Well, I think we found our Saturday Night Live soundbite," Perry said to even more laughter.
At least in one committee, humor held sway over politics.