The Season 19 The Bachelorette star, 32, and Alan, 28, dined at Avra in Beverly Hills on Wednesday, March 15 and they left the restaurant around 10PM, Peoplereported.
"They're both single. He wants to find love and so does she," a source told People.
"He asked her out. This is their first date. They haven't been out at all. He was so excited to take Gabby out."
Alan and Gabby developed a friendship on Dancing with the Stars' 31st season late last year when Gabby competed with pro partner Val Chmerkovskiy and Alan was partnered with Jessie James Decker. (Gabby and Val finished the season in second place, while Alan and Jessie placed tenth).
However Alan also served as Gabby's substitute pro partner when Val tested positive for coronavirus during the Dancing with the Stars season's "Halloween Week" round, resulting in the pair spending significant time together while Val was sidelined.
They each then joined the Dancing with the Stars LIVE cross-country tour, which just wrapped last week after 60-plus shows in three months.
"They grew really close while Gabby was on DWTS and they remained close. The hope for both of them is that something blossoms from this," the source said.
"The hope for both of them is that something blossoms from this."
An eyewitness at the restaurant told the magazine that Gabby and Alan sat outside at a private table and ordered champagne shortly after they were seated.
They were both "constantly smiling and giggling" throughout the evening, according to the eyewitness.
The eyewitness said the couple looked "so cute together and seemed to give off the vibe nobody else was in the room."
"They were very engaged in each other's conversation," the onlooker shared. "They ate fried zucchini chips and Gabby took photos of their food as Alan looked at her and smiled. They seemed very into one another."
The eyewitness also claimed Alan "often leaned in close to Gabby," who was dressed in a black skirt and matching leather jacket over a white T-shirt. Gabby also wore her hair half up and half down.
"Gabby took her phone out to show Alan something and they both smiled," the onlooker added.
Gabby -- who had repeatedly voiced to the press that she'd "of course" go on a date with Vinny if he formally asked her out -- took to Instagram in late January and posted a slideshow photos of her friends and Vinny.
Jessie James commented on the post, "Dancing with your honey @vinnyguadagnino. Can't wait to double date in Nash."
Since Jessie was suggesting a double date with her husband Eric Decker, many fans interpreted the comment to mean Gabby and Vinny had officially begun dating.
But Vinny clarified to Us Weekly that he and Gabby were not an item.
"It takes a lot more for me than just, like, a couple Instagram comments to be dating someone," Vinny explained.
"But I would go on a double date with her and Jessie and her husband. I would actually go to dinner with Gabby. It's just that we just met, you know what I mean? It's not like anything serious."
Vinny, however, gushed about how he had "great chemistry" with the former ICU nurse and NFL cheerleader.
"We're both, like, comedians. So, that's why we get along and that's also why we flirt so much on Instagram because we have that same banter with each other," Vinny shared.
Gabby told Us in early January that she and Vinny "built a good friendship" while on Dancing with the Stars and "naturally kind of clicked."
Gabby said she and Vinny initially just enjoyed stirring the pot and teasing fans with their flirtation but then the idea of dating the Jersey Shore star became a real "possibility" for her.
Gabby revealed in December that Vinny was her "celebrity crush" but he'd need to be the one to make a move and ask her out.
"You guys need to ask him [how he feels]. He's so dead to me because he hasn't been doing any press and I have," Gabby joked at the time. "I'm, like, dealing with all these questions. But he's the one who started it."
In November, for instance, Vinny playfully dubbed Gabby his "Baby mamma" on social media, and she in turn called him, "My main man."
Gabby also called Vinny a "ten" on Instagram and he quipped in reply about how she needed to stop talking about herself.
News of Gabby and Erich's split surfaced on November 4, and then Gabby revealed on Dancing with the Stars later that month how she and her former fiance weren't "in sync" or "the best match" for each other.
Gabby told the magazine that she and Erich weren't compatible once they started their lives together in the real world after being in The Bachelorette bubble.
Gabby said her stint on Dancing with the Stars was therapeutic for her as she dealt with and tried to move on from her split from Erich and rocky romance with Clayton Echard on The Bachelor's 26th season.
"She is a beautiful person, in and out, but, that didn't end up so well," Alan told Jana Kramer during an April 2019 episode of her "Whine Down" podcast.
"We met on the show, and you know, that is her whole career... she is a social media influencer. How could I tell her whether she should post something or not? You know, that's not my duty as a boyfriend. I personally am a super private person."