My overriding sentiment about Casa Mono is that it will be a very nice destination once the weather is nicer and the tables spill outside. CM is the type of place that one would like to pop into on a whim, and presently it is way too crowded to be able to reliably do that.
The food at Casa Mono is almost too flavorful. After the scallops with chorizo/tomato broth (interesting because the scallops were served in their shell) my palate was pretty much ruined for the final two courses of my meal. I definitely enjoy big flavors but found it odd that the wine list is so skewed toward expensive reds (to me, in the context of a tapas bar, $80+ is expensive) given the existence of so many mouth-crushing dishes.
Croquetas with bacalao and orange ailoli - good crunch and cod flavor to the croquetas, the ailoli was slightly too bitter orange for me.
Serrano ham with tomato bread - I've never had serrano ham sliced in thick slices before and this was interesting. Some bites were great, some were ham jerkey.
Scallops with chorizo and tomato broth - too much garlic (which takes lot for me in this context) but overall quite good. I used the scallop shells to slurp up the broth.
Grilled razor clams - probably my favorite dish. Perfect blend of grilled, citrus, and sea.
Deep fried sweetbreads - my second favorite dish, first three bites were fantastic and then I got bored.
Oxtail stuffed paquillo peppers - to me the meat could have used more acid but my girlfriend felt it was perfect.
All of these portions (individually) would fill say.. a cereal bowl. I was full but I could see how other diners could want to eat more.
$150 with a $45 bottle of Tempranillo/Cab/Merlot blend and then a shared quartino of a 91 Rioja from a magnum, $25 (excellent).