My first thought when I walked in to Diego's was that it would be typical Mexican dive bar. This couldn't have been further from the truth, though. My sister had a Groupon for it, so we stopped in for lunch. First, the place is a lot bigger than it seems from the street. The restaurant really extends back. The grill area is partially open, so you can see the cooks preparing the food. It definitely gives it a flair of authenticity.
I ordered seafood enchiladas, and my sister ordered a grilled salmon dish, complemented by a variety of grilled fruits and mashed potatoes. The food was, in a word, fantastic. More than that, it was beautiful. I wish I had taken a picture, because the presentation was gorgeous. My seafood enchiladas came with a red pepper cream sauce artfully drizzled on top, forming a zebra pattern with the cheese. My sister's dish took the prize, though. Bright strawberries, pineapples, and berries sat alongside a richly pink salmon fillet. I think we both went "oooh" instinctively when our entrees arrived.
Everyone talks up the margaritas, but unfortunately I can't speak for that. I was hung over, and I'm not a believer in the "hair of the dog" approach. But from what I understand, they are cheap and good. I am definitely looking forward to coming back and trying them.
Overall, Diego's is a welcome addition to State Street. I'm excited for my next visit to Madison to stop in again!