What can I say, Gaucho is amazing. You're going to have to wait in line, but that's a given and it's well worth it! My best suggestion is to go at an "off" time, for both of my Gaucho experiences I've arrived around 2 or 3 in the afternoon and the line is pretty manageable.
You can't go wrong with the steak plates, which come in small (6 oz) or large (12 oz). They come with a Gaucho salad and bread. The steak sandwich is also amazing if you're in the mood for a sandwich. You can pile the sandwich up with just about any topping you'd like. Additionally, they do different empanadas daily; we tried the chicken and they were pretty yummy.
After getting seated and while waiting for your food, load up on all of the sauces. They're all delicious in their own way, but the chimi is my go-to. By the time you have your sauces, your food will arrive. It's crazy fast, which is great after waiting in a long line of anticipation.
The only thing I noticed is their meat is a bit under cooked. I always order a medium steak, but at Gaucho I would go with a medium-well just to make sure the meat isn't too red.
Another win for Gaucho is their food truck Asado which can be found at popular breweries in the area throughout the week.