Op! Just saw this thread. Luckily we connected on this already, but I figured I’d post what I sent ya here, in case anyone else is interested in the future:
The Source - http://www.thesourcedenver.com/ - This is a “food market” that has a couple restaurants, shops, bar, etc. I had a really good meal at Acorn, and I see them listed highly on a lot of Best Ofs.
Union Station - http://unionstationindenver.com/ - This is also a train station, but they’ve recently renovated it and added a collection of restaurants. I’ve eaten at Stoic & Genuine and thought it was solid. Might be odd to think of going to a seafood restaurant in Denver, but supposedly they go to a lot of effort re: sourcing and their exec chef is a Wolfgang Puck-alum, for what it’s worth. Bonus points for Union Station being close to the main downtown/Larimer Square. My friend also said good things about Mercantile, but I’ve never been.
Chef Bonanno - Mizuna is the flagship restaurant of chef Bonanno’s Denver empire, and I had some really good meals there. Bones might be worth trying, if you want to see what Ramen in Denver is like Green Russell is his speakeasy bar in Larimer Square, which I think is a cool spot. You go down some stairs, enter through a butcher, and they often have live jazz.
Chef Tommy Lee - Uncle is the place to go if you’re curious about Denver’s take on Momofuku. I remember my bowl being good. His new restaurant Hop Alley says they do traditional regional Chinese, and my friend says it’s getting really popular.
El Five - https://www.elfivedenver.com/ - My friend won’t stop taking about the paella he had there. I haven’t been, but it appears to be a tapas place. I also saw this as Eater Denver’s #1 hottest new restaurant.
Frasca - http://www.frascafoodandwine.com/ - This is my one Boulder recommendation. Italian. And walking distance from the Pearl Street Mall. Although, apparently Basta in Boulder is good too.
Guard and Grace - https://guardandgrace.com/ - If you’re looking for a steakhouse, this is a good one.
Great Divide Brewery - http://greatdivide.com/ - This was always my favorite brewery. They didn’t have food when I lived there, but they’ve since expanded and now have a kitchen, I believe. But go for the beer, if that’s your thing.
Local Favorites - Finally, here are some spots that are specific to CO. Think Tito’s Tacos. The first is Santiago’s, who does green chili and has several locations around the stat. The second is Beau Jo’s Pizza, which is famous for their huge crust that you dip in honey. It’s wild. Chipotle. Just kidding, but the first location was in Denver. Bonnie Brae Ice Cream - Quaint little homemade ice cream place, with great peppermint. Oh, and don’t eat at Casa Bonita. But if you do, try to let you order two kids chicken tender meals, as they are the only edible items (other than the sopapillas).