But "it was just a friendly lunch," a source told the entertainment news site.
The taco spot is the same place where they were caught kissing back in October 2012, Daily Mail reported.
This is not the first time the duo was seen in public together after splitting last year. A source told People, that the 33-year-old "Avengers: Age of Ultron" star and the 34-year-old "Almost Human" actress have been spending time together in recent months.
Just late last month, the on-and-off couple also spent some quality time with Evans' family at Lavender Asian Cuisine & Bar in the actor's hometown of Sudbury, Mass, according to People.
"It looked like a family night out," a fellow customer said. "They were with a bunch of people, including Chris's family, and Chris and Minka sat in the back while other people in their group got up and did some karaoke."
"[The rumored couple] looked like they were having a great time," added the eyewitness. "They all got into the locals singing karaoke."
A second eyewitness told the magazine: "They sat next to each other, they were off in a corner, having drinks and keeping to themselves but still part of the group. They kept a very low profile. They're really cute!"
Evans and Kelly briefly dated in 2007 before getting back together in 2012. However, they broke up for the second time in October last year because work commitments kept them apart.
"It didn't make sense for them to be together right now," an insider told Us Weekly of the couple. During that time, Kelly was filming "Almost Human" in Vancouver, British Columbia, and Evans was planning to direct the movie "Before We Go" in New York City.
After their 2013 split, Evans was linked to his childhood crush Sandra Bullock after they were spotted together at several public outings. While the "Captain America" star never commented on romance rumors between him and the "Gravity" star, the 50-year-old Oscar-winning actress laughed them off in June, saying, "We've since married and it started breaking apart, so we separated. We filed for divorce, and I hope everyone can respect our privacy. But we're going to remain friends and share responsibility of the farm animals we've taken on, because you just can't abandon the animals."