On the evening of the first Saturday of every month, you can often find me and my sweetie aboard a 100+-year-old ship at the Hyde Street Pier in San Francisco bellowing out melodies among hundreds of other voices. We are not part of some freakish cult (at least, not in so many words). We merely participate in a 30-year-old San Francisco tradition: the Hyde Street Chantey Sing.

For the past thirty years, singers of all ages have been gathering aboard the Balclutha to belt out working songs of the sea. Chanteys are fairly simple tunes that are largely call-and-response and easy to catch on to. Once you’ve been to a couple of chantey sings, you’ll be familiar with most of the songs commonly sung.  The acoustics on the ship are excellent, the singing is top-notch, the vibe is fun and friendly, and after 11 p.m., the session opens up to include ballads and bawdy songs, which are definitely worth sticking around for.

But the best thing about the chantey sing, in my opinion, are Irish coffees from the nearby  Buena Vista  to warm you from the chilly, San Francisco bay air.

Leave the warm, covered deck of the Balclutha and walk to the end of the pier, past the creaking ships and slapping waves. Cross the street and shove your way into the ever-crowded Buena Vista, where Irish coffees were tested, perfected, and popularized 60 years ago on November 10th, 1952. Belly up to the bar, order their iconic beverage, and the bartender will present you with a cup of perfectly sweetened, highly boozy coffee topped with softly whipped cream.

After several chantey sings (and perhaps several Irish coffees), I reckoned that the winning combination of coffee, cream and Irish whiskey would make a stellar frozen dessert, and began working them into an ice cream. But I didn’t realize that the ice cream would require such a delicate balance of ingredients to showcase the coffee and boozy flavors and still set into a scoopable ice cream.

I began by consulting my ice cream bible for coffee- and booze-to-custard ratios and adapted them to my favorite ice cream formula. But as I churned up the ice cream, which wasn’t as boozy as I would have liked it, I realized that I should have decreased the amount of fat in the custard to both accommodate more alcohol and to mute the flavor of the coffee less. Fat, alcohol and sugar all prevent ice cream from freezing. Adding more of any to your ice cream will result in a more pliable product, but too much and your ice cream will never solidify beyond the milkshake stage. Fat and dairy also have the effect of softening flavors, which make it a perfect match for potent ingredients like coffee and chocolate, but too much prevents the flavors from shining through.

So for trial 2, I took down the fat content by subbing in whole milk for the half and half, and added more whiskey. But this batch tasted icy and thin, with the coffee flavor too harsh from the leaner base.

For batch 3, I split the difference, still using some whole milk but adding more cream. This ice cream took 5 tablespoons of whiskey but still firmed up to a pliantly scoopable texture. As the ice cream churned, I held the whiskey bottle and asked my other half if I should add more. ‘It’s still not boozy enough,’ I lamented. He laid a hand on my arm. ‘The problem is, it will never be boozy enough. But! You can always pour more whiskey over your bowl of ice cream.’ He’s so smart.

I’m glad I listened to him, because the ice cream was difficult enough to photograph. Straight from the freezer it is perfectly creamy, but scoops begin to melt within minutes, making challenging subjects.

Coffee ice cream is a favorite of mine, and this version rivals the best with its creamy texture, earthy coffee flavor, and boozy bonus. I used a dark-roasted swiss water decaf, made by the folks at  Coast Roast  in Tomales, CA, so I can eat as much as I want for dessert without getting the jitters.

This ice cream makes a heavenly treat by itself, but it would also make a heavenly pairing with chocolate bouchons.  And save your egg whites to bake into a luscious cake, such as buckwheat-hazelnut, chocolate pistachio  or chocolate hazelnut.

If you lack an ice cream maker, don’t fret: try David Lebovitz’ method for making ice cream without one. This recipe is particularly amenable to the hand-stirring method what with all that booze that prevents it from freezing solid.

Share this ice cream with friends, and you may unwittingly start a cult of your own; it may or may not involve singing.

Irish Coffee Ice Cream

Give yourself 1-2 days to complete this ice cream, but know that the time is mostly inactive: 1 hour to steep the cream with the coffee beans, 4 hours to chill the ice cream base, and several hours to overnight to firm the churned ice cream in the freezer.  If you lack an ice cream maker, check out David Lebovitz’s post on making ice cream without one. And if you lack a vanilla bean, add 1 teaspoon of vanilla extract along with the whiskey.

Good coffee ice cream starts with good coffee; I used a dark-roasted swiss water decaf (from Coast Roast in Tomales, California) so that I can eat this for dessert and not get the jitters. For the whiskey, I use Jameson, which is my current favorite drinking whiskey, but use what you like – bourbon or dark rum would probably be tasty substitutes (though the ice cream will no longer be ‘Irish’). The amount of whiskey here creates an ice cream with a soft set that (unfortunately) doesn’t taste strongly of booze; but don’t be tempted to add more, or your ice cream may not set at all and end up like a creamy slushy. If you want more whiskey flavor (and really, who doesn’t?) splash it over individual scoops; or float a scoop in a mug of real Irish coffee.

Makes about 1 quart

1 1/2 cups heavy cream

1 cup plus 2 tablespoons whole coffee beans

1/2 vanilla bean, split and scraped

1 cup whole milk, plus a few extra tablespoons for topping off the cream (see directions, below)

4 egg yolks

1/2 cup sugar

pinch salt

4-5 tablespoons whiskey (see headnote)

Combine the cream, coffee beans and vanilla pod and scrapings in a medium saucepan. Warm over a medium flame, shuffling the pan occasionally, until the cream is steaming and bubbles form around the sides of the pan. Remove from the heat, cover, and let steep for 1 hour, shuffling the pan a few times during the hour to evenly saturate the beans.

Strain the cream into a 2 or 4-cup capacity measuring cup. Slowly pour enough whole milk  over the beans to bring the mixture back to 1 1/2 cups, rinsing the beans with the milk. Press on the beans to extract any extra liquid, then discard the beans. Chill the infused cream while you make the custard. (The cream can be infused ahead of time, covered, and chilled for up to several days.)

In the now empty saucepan, warm the remaining 1 cup of milk until it is steaming and small bubbles form around the edges. Whisk together the egg yolks, sugar and salt in a medium bowl to combine and anchor the bowl on a damp towel. Slowly drizzle the hot milk into the yolk mixture, whisking constantly, then return the mixture to the saucepan. Cook over low heat, stirring constantly with a heatproof spatula, until the mixture starts to ‘stick’ (form a film on) the bottom of the pan, and/or registers 170 º on an instant read thermometer. (This will only take a minute or two.) Immediately strain the custard into the coffee-infused cream. Optionally chill the ice cream base over an ice bath.

Now for the important bit:  stir in that whiskey!

Cover and chill the base in the fridge for at least 4 hours, preferably overnight, or up to 3 days (I like to put it in a 1-quart, wide-mouth mason jar.)

Place the ice cream base in the freezer for half an hour to get it really cold, stirring (or shaking, if in a mason jar) it every 10 minutes. (I also like to place the vessel in which I will be storing the ice cream in the freezer to get it cold so the churned ice cream doesn’t melt on contact.) Spin the ice cream in an ice cream maker according to the manufacturer’s instructions. The ice cream will still be fairly soft when it is done churning, about the consistency of a thick-ish milk shake, but it will firm up in the freezer.

Glop the ice cream into a large jar or loaf pan, cover, and freeze for at least 4 hours, or preferably overnight. The ice cream will still be pliant, but should be firm enough to scoop.

The ice cream is best within the first few days of churning when ice crystals are at a minimum, but it will keep, covered and with a piece of parchment paper pressed to its surface, for a month or two.

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