One of, if not the O-G specialty coffee espresso blends, Black Cat, from Intelligentsia Coffee is a syrupy sweet and easy to work with espresso blend.  Currently comprised of Brazilian and Colombian coffees, pulling shots of Black Cat is like welcoming an old friend.  Shots are always like a sweeter version of a thoughtfully roasted Northern Italian espresso, with a bit of roasty body and plenty of dark chocolate and nutty undertones.  Black Cat typically sneaks in a bit of fruit, acidity, and more sweetness in place of roasty notes to keep it a bit more current, but it's always good straight or with milk.  

Straight shots taste like dark caramelized sugary syrup that coats your mouth and has just hint of bakers chocolate or cocoa powder.  Intelligentsia recommends pulling shots at 18 - 18.5 grams in to 34 - 40 grams out in 25-30 seconds at 200*F.  The coffee is certainly versatile and easy enough to work with to suit all of those parameters though I found my favorite shots were pulled at:

• 19 grams in an IMS 16/20 Precision Double Basket
• 31-34 grams out in 27 seconds, using 198 - 200*F water.

The coffee will hold up and not prematurely blond to pull longer shots at higher yields, though I found this started to introduce more of the roasty and nutty flavors, which may compliment a larger milk drink well.  I found keeping the shots a bit shorter helped coax out a touch of acidity and produced a really thick, syrupy, mouth-coating shot.  I prefer to use the IMS or even a stock double basket with more comfort blends like this, as I find it can be really easy to over extract or "turn up the treble too high" so to speak with the VST basket.  The IMS basket is deeper and holds more, which is why I typically use around a 19 gram dose with it.  

Paired with milk, more flavors of chocolate come forward, specifically dark chocolate.  Black Cat will hold up in large milk drinks, which is a good reason why it's Intelligentsia's staple bar blend, though I found my favorite balance to milk in the 5-6 ounce range for a rich sweet and creamy cappuccino.  

Available for a very reasonable $15 for a 12 ounce bag with free shipping on orders over $40 here.  Be sure to try out the Black Cat Organic as well, which typically has a bit lighter/sweeter/brighter profile and their seasonal Sugar Glider, which usually proves quite interesting.