“Fennel cooked sous vide epitomizes the advantages of using this technique for vegetables. Placed in the bag with some tarragon and Pernod, it absorbs flavor without giving up any of its own to the cooking medium – as would happen if it were braised. Its shape means that the broad base and thick stalks may not be fully cooked by the time its more slender ends are – i.e., it’s easy to overcook and undercook. But with sous vide, once the thinner parts of the vegetable hit perfect doneness, they stay there, without overcooking while the thicker parts cook through. And the fennel comes out of the bag pristine, it hasn’t gotten beaten up by the agitation of the water as can happen when cooked conventionally, and it slices beautifully. But be aware that the aromatics in the bag have a powerful effect and if you’re not careful, the vegetable can taste only of Pernod.” - from Under Pressure by Thomas Keller
The Advantages/Benefits of SousVide
Quotes from this article by Amanda Hesser
”When it comes to things like artichokes, steaming and boiling and braising are fine, but there’s a great loss of liquid as it cooks — which is another way of saying a great loss of flavor because the juice of the artichoke itself, while mostly water, is very flavorful. Sous vide eliminates this loss, and hence the sensation that you’re tasting a true artichoke — not just a delicious artichoke, but an artichoke the way it was intended to taste.’‘ - Dan Barber, the chef and owner of Blue Hill
The following is a guest post, recipe and photos by Brenda (@mightyvanilla).
Sous vide is the technique of sealing food in a bag and cooking it in a water bath at a constant temperature for a fixed amount of time. It’s more known as a cooking method for meat and eggs, but I also like using it for fruit and vegetables because the cooking time is much shorter and it produces interesting flavours and textures. When I read the above passage in the Under Pressure cookbook by Chef Thomas Keller, I knew I had to try it.
I think of sous vide as two primary steps: sealing the food in a bag, and cooking the sealed food in water. There are several home products available that are used to achieve the first step and the majority of them work by pressing the end of the bag closed with a lid, sucking the air out which simultaneously pulls the bag around the food, and heat sealing the bag. This type of system works reasonably well for most foods but it doesn’t work successfully when liquids are involved because the suction mechanism will pull liquid out and prevent the bag from getting a clean seal across the entire opening. In order to seal a bag containing liquid, plus remove the air inside, both the bag and the sealing mechanism must be fully enclosed in a chamber and then all of the air must be pulled out of the chamber prior to the bag being sealed. Since the pressure is the same on the inside and outside of the bag, the liquids stay inside the bag and don’t get pulled out. When enough air has been removed from the chamber, the sealing mechanism activates, the bag is sealed, and then air is allowed back into the chamber. Since the pressure inside the sealed bag is now much lower than the chamber pressure, the bag compresses itself around the food. This type of device is known as a chamber vacuum sealer and they’ve been used by restaurants and commercial food preparation kitchens for many years. Usually they’re large and heavy, are several feet high and wide, and not practical or cost effective for home use.
Like many other restaurant concepts that get adopted for personal kitchens though, chamber vacuum sealers have made their way to the home market. The VacMaster VP112 is a smaller home-sized version but its chamber is still large enough to hold a whole 4lb chicken. (The footprint of the chamber is quite sizable but the height can be a limiting factor if you want to seal very large pieces of meat.) The adjustable pressure also allows delicate foods to be sealed at a partial vacuum so that they don’t get crushed and bruised. That is, unless you want them to be – this is how you make compressed fruit and vegetables in modern dishes. (I’ve had my VacMaster VP112 for several years now and use it for much more than sous vide. It’s great for storing excess stocks, soups and sauces, freezing summer fruit, and keeping extra garden produce. I also prefer to buy meat whole or in larger cuts and will use it to portion food into meal-sized amounts.)
When sealing anything that contains liquids, it’s best to remove one or more plates from the chamber so that the liquid level is noticeably lower the sealing bar. When not sealing liquids, the plates should be left inside the chamber so that there is less air for the machine to remove. I’ve found that a setting of 40 seconds is long enough to pull enough air out for most things, regardless of whether the bag contains solids, liquids or both. I also like that the seal can be activated at any point once the air has started to be pulled out. For example, if you see that the liquids are vigorously ‘boiling’ from the low pressure, you can press the Stop button and the machine will seal with the low pressure that it’s already achieved.
The fennel salad recipe called for two preparations of fennel: one where pieces of fennel bulb and baby fennel were sous vide in a marinade along with an herb sachet and then seared just before serving, and another where the fennel trim was sous vide before being pureed.
Baby fennel is difficult to find at the store and it’s too early for young local fennel so I adapted the recipe and only used large fennel bulbs. While the fennel marinade called for Pernod and star anise, I decided to use absinthe that I had on hand that already tasted strongly of licorice. (Vacuum sealing is a great way to infuse more flavour into food – the vacuum ‘pushes’ seasonings and marinades into the foods and it can result in a stronger than normal taste.) After being cooked in a water bath, fennel has an intense and smooth flavour with a firm and yielding texture. Caramelizing them in a hot pan adds additional flavour, texture and colour contrast.
Since I only used large fennel, the puree that was made from the sous vide trim ended up being slightly fibrous because the green stalks were quite tough. The recipe calls for pureeing the cooked fennel trim in a VitaPrep until it’s the consistency of a smooth sauce, but I think this component would work better with younger and more tender fennel stalks. Even though the puree was blended in the VitaMix for a longer period of time, some fibrousness remained and the liquid started to separate out from the solids. The puree was still very tasty though, so I strained the excess liquid out and added the puree to each plate as a small scoop rather than a sauce.
For the almond puree component, the recipe called for Marcona almonds which are a particular variety of almond that is grown in Spain. It’s recognizable by its rounder and flatter shape, and has a more complex and intense flavour than regular almonds. Since it’s a specialty type of nut, it can be harder to find and more expensive. If Marcona almonds are not available, a good quality almond can be substituted. To make the puree, roasted Macona almonds were simmered in milk for an hour and a half (or longer if necessary) and then blended in a VitaMix with some of the simmering liquid. I ended up using all of the simmering liquid so that the blender could be left on high for long enough to get the smooth puree. (I’m still learning how best to use a VitaMix and find that it’s a balance between adding enough liquid to get the mixture to move versus adding too little and overheating the machine.) The recipe called for pushing the puree through a fine mesh but I tested this with a small amount and found that it made no difference to the texture, the VitaMix had already made it smooth enough. But since I had blended all of the simmering liquid in, the puree wasn’t quite thick enough to form a scoop like the one shown in the book so I used it as a generous smear on the plate instead.
Okay, I have to mention how delicious the Marcona almond puree was! The amount of puree that the recipe made is much more than the salad actually needs but it was well worth the effort and I’m glad there was a lot left over. The puree was smooth, nutty, rich, salty and tasted intensely of roasted almonds. It was so good that I was eating it straight with a spoon, and I’m already thinking of trying the procedure with roasted hazelnuts.
For the last major component of the salad, the orange confit, I used a mixture of blood and naval oranges and twice as much as the recipe called for. Orange is a classic pairing with fennel, and the sweetness and colour of the extra pieces contrasted nicely with the dark caramelized fennel wedges, the light fennel puree, the smooth and nutty almond puree, and the salty crunch of whole almonds.
“Herbs, spices, and garlic should not come in direct contact with food that is vacuum-packed and cooked sous vide, as the flavour will be stronger in areas where there is direct contact. To avoid this, we make sachets, which allows the flavours to infuse the other ingredients evenly.” - from Under Pressure by Thomas Keller
- Adapted from Under Pressure by Thomas Keller
Serves 4 as a starter course
Sous Vide & Caramelized Fennel
Notes for Success:
Sous Vide Fennel
Trim the root ends of all the fennel.
Remove the outermost layers from the 2 medium fennel bulbs and set them aside for the puree. Cut off the green tops and reserve about 2 Tbsp of the fronds for garnishing at the end.
If you have baby fennel, cut off any dark tips on the diagonal and make a slit in the bottom of each bulb for even cooking.
Stand the medium fennel on its root end and cut evenly in half. Place each half cut side down and cut it evenly into 1/2 inch wedges. Remove any remaining fronds from the wedges.
In a medium bowl, whisk together the Pernod, olive oil, and salt.
Put the fennel wedges and baby fennel in separate bowls and divide the marinade evenly between them. If you don’t have baby fennel, place everything in one bowl. Toss well to coat.
Make two herb sachets by dividing the tarragon, thyme, bay leaf, star anise and caraway seeds between two sheets of plastic wrap. Roll up the sachet, and cut off the ends of the roll so that the herbs are just covered. Place each type of fennel, with its liquid, in a separate bag. Add a herb sachet to each one and vacuum seal them. If you only have fennel wedges and no baby fennel, just make one herb sachet and seal all the fennel in one bag.
Sous vide the fennel at 85C (185F) for 40 minutes, or until tender. Chill the bags in an ice bath.
Place the fennel into a bag and vacuum seal.
Transfer the almonds to a saucepan and add the milk and salt. Bring the mixture to a simmer and simmer gently for about 1 1/2 hours, until the nuts are soft enough to puree. If the liquid reduces below the level of the nuts, add water to just cover the nuts. Keep a close eye on the milk to make sure that it does not stick to the bottom of the pot and burn. If the milk starts to stick to the bottom, turn the heat down and cook the almonds for a longer amount of time. The almonds should have no crunch left before pureeing.
Drain the almonds and reserve the liquid.
Put the nuts into a Bellini and, with the machine running, begin adding enough liquid to allow the nuts to spin. Continue to add more of the remaining liquid as necessary and blend on high speed for several minutes, stopping to add additional salt to taste and to stir the puree from time to time, until you have a silky smooth puree. If the puree is not smooth enough, push it through a chinois or fine-mesh conical strainer.
Place the puree into a covered container and refrigerate until serving time.
To cut supremes from the orange, use a sharp knife to slice the top and bottom away and stand the orange on one of the flat ends. Following the curve of the orange with the knife, cut the white pith and peel away in large strips. Hold the orange over the container and place the knife right up against one of the membranes that separates the slices. Cut to the center of the orange, and repeat for the other membrane that holds the orange segment together. The orange segment (supreme) and juices will fall into the container. Repeat for the rest of the orange.
Combine the water and sugar in a small saucepan and bring to a boil, stirring to dissolve the sugar.
Pour the hot syrup over the orange supremes and let them cool to room temperature.
Spoon some fennel puree and almond puree onto each plate.
Divide the caramelized fennel, baby fennel, and orange supremes evenly between the plates.
Sprinkle a light dusting of caraway seeds and salt over the fennel pieces.
Garnish with the toasted almonds, microgreens, and fennel fronds.