It’s not every day that a new bar opens featuring a fairly esoteric and nerdy spirits list — and helmed by a non-drinker! But given Israel Idonije’s impressive diversity of interests, it’s not surprising that when he started digging into the history and culture of amaro, he got excited even without tasting them. Buttercup, his upcoming South Loop bar (75 E. 16th St.), will focus on the Italian bitter spirits.

Sports fans probably know Idonije from his time playing for the Chicago Bears, but recently he’s been focused on opening restaurants. Buttercup is his third restaurant in the South Loop, following on the heels of The Staley and Signature Steak. When he’s not working in the restaurant, he also is a comic artist, a sports team owner, a philanthropist, and more.

“I live in the South Loop, I love the neighborhood, it’s a gem,” explains Idonije. “But if you want to do something sexy or catch a vibe, you are going to leave the neighborhood.” As a former South Loop resident myself, I see his point; despite abundant commercial property and tons of people, the neighborhood has just never quite managed to take off. Idonije has already been working on changing that with his other locations, and Buttercup is taking the next step. The spot isn’t just a bar; it’s also going to be open as an all-day café space. From 7 a.m. to 2 p.m., the bar will feature coffee from Sparrow Coffee, pastries, and baked goods. From 4 p.m. to late into the evening, it transforms into a cocktail bar with light bites.

Buttercup is located in the space of the former 16th Street Bar, a longtime neighborhood haunt. “I got a lot of messages when we bought it. 16th Street Bar was a cornerstone in the neighborhood, it was like Cheers,” says Idonije. “My hope is we can make this the place for people to go to work in the café during the day and come unwind and people watch at night.”

Like Idonije works with Stephen Gillanders on The Staley and Fabio Viviani Hospitality Group on Signature Steak, for Buttercup, he’s working with beverage director Luke DeYoung and chef Alex Carnovale of Oliver’s. They’re keeping the menu at Buttercup fairly simple. In addition to an amaro list and a selection of classic cocktails, the food menu includes charcuterie, a truffle pizzetta with fontina, a roasted garlic kale Caesar salad, anchovy toast, and a roasted pork collar. Buttercup also features a fancy imported Italian shaved ice machine, which will be used for iced coffee in the morning and iced amaro in the evening.

If diners aren’t familiar with amaro, they can fall back on the classics, but even Buttercup’s classics will come with an amaro twist; a Manhattan becomes a black Manhattan with the addition of Amaro Ramazzotti, and a daiquiri turns into an amaro daiquiri with Aperol. One of the most fun sections of the menu is a “choose your own adventure,” featuring a list of amari and mixers, so customers can create their own drink — Cynar and Aranciata or Meletti and tonic.

The ”official” opening day is September 14, though as with all restaurant openings, check before you go in case there’s a delay.