There is just no mistaking this alligator sweater and legwarmers feeling in the air. It’s autumn through and through, and for those of us who missed out on summer proper, it isn’t exactly a welcome shift. Nonetheless, it’s important to make limoncello when life gives you lemons, so I’m going to plunge Hunter Wellies-first into a cauldron-sized frenzy of soup-making. This bisque in particular showcases the delights of harvest season- successfully marrying potatoes, artichokes, leeks and carrots. Toss in a little bacon binding and some tarragon for flair, and you’ve got a soup you’d be proud to introduce to your mama but you also want to feel up in the back seat of your Corvair.
The ingredients are rustic. I’m kind of tossing around the back-to-the-basics approach this week. The way they’re combined, however, is anything but. I know, I know, I wax lyrical about the endless capabilities of sous vide entirely too much, but I haven’t had much of a chance to tell you about sous vide and soup. Sous vide and soup were meant to meet on EHarmony, have babies, and make sloshy love together for the rest of their lives. It’s a perfect way to commingle flavors over a long period of time without “grandma-ing” the vegetables beyond recognition. It’s also incredibly easy to simply toss everything in a bag and walk away while the wonder of water works its witchy ways. It is important to choose ingredients that are best cooked at the same temperature; for example root vegetables with other root vegetables. Raw onions and garlic do not come out so well sous vide, so I always sauté them first or add homemade garlic/onion powder instead. In this case I sautéed the leeks with the bacon, before adding them both to the bag.
Recent readers will know I recently knocked into an at-home molecular gastronomy kit and I’ve been spherifying up a storm. What the hell does that mean? Basically it’s the fine art of turning something that is typically liquid into a ball that is taut on the exterior but still remains liquid inside. It’s done with a precise combination of two odorless, flavorless compounds- sodium alginate and calcium chloride (yes, gastronomists, it can be done other ways, but for the sake of simplification, bear with me). Carrot spheres are like great gushes of carnal lust- vulnerable, quivering until they give way and burst in one crashing, ecstatic instant. They are the perfect complement to this soup because texturally they add lightness and the sweet, cool mouthfeel is like running through damp grass on a hot day.
If you are really interested in spherification you can read up on the subject as well as gain access to a grip of recipes in this somewhat technical document. The basics are these: juice your carrots. Weigh the juice and add in .5% sodium alginate whilst whipping madly with an immersion blender. Let the bubbles settle and the juice thicken a bit in the refrigerator while you make the calcium chloride bath, which is one liter of water per 6.5 grams of calcium chloride. You can then drop the carrot juice into the bath using a syringe, a dropper, or a handy dandy pipette that drops in nearly a hundred at a time. Scoop them out after about 30 seconds using a slotted spoon, and rinse in a cold water bath. I experimented a bit with making both caviar-sized and gnocchi-sized balls, which made for good contrast in the ratio of soup to carrot. They are fairly heat-resistant, though I kind of buffered them from the hot soup by adding a layer of crème fraiche. As a study in temperature, texture and flavor, this dish succeeds mightily. It has the added benefit of taking advantage of local bounty, albeit with a modernist flair.
Sous Vide Potato Leek Artichoke Soup
3 hours, start to finish
- 1 artichoke, trimmed of leaves, choke removed ( I use a melon baller for this)
- 1 leek- white only, sliced into 1/4” rounds
- 8 oz bacon, roughly chopped
- 2 lb new potatoes
- 2 c chicken stock (frozen is easier to seal in bag)
- ¾ c heavy cream (frozen is easier to seal in bag)
- 2 sprigs fresh tarragon
- Salt and pepper to taste
Preheat sous vide bath to 185° F. Fry the bacon in a medium skillet until fat renders. Add the leek and sauté for 4 minutes, stirring occasionally. Prepare a large, food-safe vacuum sealing bag and add all ingredients except tarragon and pepper. Seal the bag and immerse it in the water bath for 2-3 hours. Remove from water bath and puree in blender along with tarragon and pepper. Serve with a dollop of crème fraiche and carrot caviar.