Just when fans — and Robert Irvine himself — thought they'd seen it all on Restaurant: Impossible, an unprecedented mission presented itself in Illinois: Not only was Robert tasked with overhauling a restaurant, but he also had to focus on the expansive grocery store that houses the eatery. Just outside of Chicago, Zest Bistro is a four-and-a-half-year-old business located within Lemon Tree Grocer, which was founded by best friends Shaun Black and Tim Canning. While the guys thought they'd have the chops to make their double-duty business work on account of their respective pasts as a produce broker and a chef, they soon began spending far more money than they earned and were forced to look to Jessica, Tim's wife, to help Lemon Tree. Ultimately, however, when they realized that her support wasn't enough, it was Robert who could give them one final opportunity. In true Irvine fashion, this monstrous challenge only served to inspire Robert more, and sure enough, he relaunched both Zest Bistro and Lemon Tree with wild success. Read on below to hear from Shaun, Tim and Jessica to find out how the businesses are doing today.

According to Shaun, "Sales in Zest are up approximately 30 percent from last year during the same time period," and Tim adds that there are "45-minute waits at times."

All three team members were wowed by updated design that Tim calls "so clean-looking," and for Shaun, "the server station" is especially exciting, as he explains that "it makes an enormous difference."

As for the grocery store, Tim notes, "The place is busier all around, and our regulars are hanging out longer than they ever have." He adds, "Everyone is really curious to see the beautiful changes made to Zest Bistro, and they usually end up taking a few items home with them from the grocer too."

Robert suggested tweaking the prepared-foods display, and Jessica and Tim explain that these ready-to-go items are indeed popular with guests. "The new deli items that Robert recommended have been doing really well. He added much-needed color and vibrance to the case," Jessica says. "Now people are really drawn into our prepared foods."

Jessica notes that the dynamic among her, Tim and Shaun continues to be a work in progress. "Our relationship is continuing to grow, and of course it takes time, but we are working on open and honest communication. One team is better than two," she admits. Similarly, Shaun adds that the most-important lesson he heard from Robert was to "talk about everything, even the hard stuff."

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