I must admit to receiving a certain thrill when a customer orders a cappuccino. When the word "dry" enters in to the picture, I get some mixture of focused and giddy. It would be hyperbole to compare this state to the proverbial "zone" an athlete enters before a competition. But although it's not the same sensation, it's not totally dissimilar either.
I am excited, first of all. Excited, both because there is someone out there who like foam as much as I do, and because I get to prepare said foam.
Though I've made it clear before, it's something that cannot really be overstated: I like steaming milk. I'd park myself behind an espresso machine, preparing a drink a minute all day, if only a thousand bits of circumstance didn't prevent it. But when someone orders a dry cappuccino, those circumstances drift to the periphery, and I'm free to engage the milk with the proper attentiveness.
Though, as with any drink, there are certainly more than one way to prepare this beverage, this is my way - and I think, of course, the best.
Pour the milk in a bigger pitcher than you think you'll need. If the milk fills the pitcher more than 1/3 full, you're in trouble.
Dip the steam wand just below the surface of the milk, and open fire. That soft, gentle hiss you expect when steaming milk for a latte will emanate. Normally, that's the goal. Here, you want that hiss a tad more violent, and with an occasional spit.
You need to stretch the milk a lot; and in order to do so, you need to drop the pitcher pretty quickly. But go too quick, and you have giant bubbles, not quality foam. If you're doing it right, the milk should still be hissing and spitting, as mentioned above, but doing so in a relatively uniform manner.You should also be able to visually gauge where the tip of the steam wand is. Keep it just below the surface of the milk, not submerging the whole head, not pulling all the way out.
Once the pitcher begins to fill, you should feel a warmth building on the side. Once you've got the quantity of foam to make the desired drink, let the wand submerge. I'm not a fan of plunging all the way to the bottom, as some are. I think it's better to simply let the elevating foam cover the wand. This helps texture the foam you've created, and prevents excess rolling. Continue steaming until you hit 140-150 degrees, then stop, and set the pitcher down.
Then, and only then, should you go about pulling your shots. Setting the milk down gives the foam time to separate and settle, which makes for easier preparation. Once the shots are pulled, you go about scooping the foam in to the cup. A bigger spoon works better here. Now, it should be said, I normally think using the giant spoon to assist in milk pouring is a mistake. But here, when you don't want to pour any milk at all, it really is the only way. So yes, you scoop the top layer of foam, and dollop it on to the espresso. Fill the cup, and be generous, because foam doesn't really spill.
If you've done it right, the cup should very light, almost as if it's still empty. Ideally, the customer will notice this when they lift it, and offer you some sort of congratulations. Dry cappuccinos are often botched, so the demanding customer is often very appreciative. At this point, there is nothing to do but graciously accept your thanks, offer your best "All in a day's work", and move forward -- hopefully with a new usual customer created.