"That's actually a Christmas miracle song because I was actually at Blake's ranch," Stefani told host Jimmy Fallon. "It's this fenced-in, high fence, with all kinds of exotic animals. I mean herds, acres."
"I was like, okay, I'm going to go for a run. I'm not only going to do my exercise, but I'm going to do my spiritual exercise. I'm going to jog and I'm gonna pray and that was like, my goal," she recalled.
"I started thinking about, 'If I wrote a Christmas song, what could it be?'"
"Then, like a nerd, as the wildebeest were passing by ... I was running and I was like, "Ooh, maybe I'll just try singing something, maybe something will come,' and the whole chorus to the song 'Christmas Eve' came," the star said.
"It was like a prayer."
"You Make It Feel Like Christmas" features "Christmas Eve" and 11 other songs, including the title track, which Stefani recorded with Shelton.
The singer said she plans to get Shelton an oversized couch for Christmas.
"I think that because he doesn't fit in any of my furniture at my house -- he's too big -- I'm like, 'Yeah, okay, I'm going to get you a couch,'" she shared. "I try to make him feel comfortable in L.A."
Stefani released "You Make It Feel Like Christmas" in October.
She and Shelton previously collaborated on the song "Go Ahead and Break My Heart," which Shelton discussed with People in April 2016.
"This song's important to us and the fact that we wrote it together is so important to both of us," the country star said.
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