The cringeworthy 2011 moment when Rick Perry couldn't remember the name of the department he is now tapped to lead

President-elect Donald Trump has tapped former Texas Gov. Rick Perry to run the Department of Energy - a department he was unable to remember in what became an infamous moment from the Texas Republican's failed 2012 presidential campaign.

During a late-2011 Republican primary debate on CNBC, Perry said he would eliminate three cabinet-level departments should he be elected.

He could name the Departments of Commerce and the Department of Education, but was unable to name the third. 

"It's three agencies of the government that when I get there that are gone," Perry said. "Commerce, Education, and the uh, um, what's the third one there, let's see."

Former Rep. Ron Paul of Texas was standing next to him, trying to help out, and another candidate interjected that it was the Environmental Protection Agency, which Perry then joked was the third one he couldn't think of.

But then he was further pressed by CNBC's John Harwood about the matter, and Perry could not recover in the slightest.

"Is EPA the one you were talking about?" he asked.

"No sir," Perry responded, to which Harwood asked "But you can't name the third one?"

"The third agency of government I would do away with, Education, the uh, Commerce, and let's see," Perry said. "I can't the third one. Sorry. Oops.

Watch the "Oops" moment below