I first spotted this recipe in A Day At elBulli several years ago, and thought it was just the most magical thing ever. The idea here is terrifically simple: some sugar is melted gently in a saucepan, and a metal ring cutter is dipped into it and lifted out such that a film forms across the opening of the cutter (sort of like dipping a bubble wand into a container of soap). Then, a dollop of flavored oil is dropped into the ring mold. The (relatively-cooler) oil firms the sugar film slightly, and as the oil falls, it tugs the sugar film down with it, enveloping the oil in the sugar. The result, if done carefully, is an incredibly-thin ‘candy shell’-wrapped spoonful of oil.
I’ve tried a few variations on this idea in the past, with mixed results. For a dish I once tried to build involving gooseberries, rum, rosemary and peppercorns, I tried dropping peppercorns through the sugar film, but because they were so light they didn’t really pull the film down and envelop themselves the way I’d imagined. A second attempt, this time involving tapioca pearls that had been cooked in Skittles stocks, worked a bit better but ultimately proved to be far too delicate to actually be useful in a restaurant context: the water in the pearls dissolved the sugar shell just seconds after they’d been formed.
So the success of elBulli’s version relies on both the weight of the oil to properly stretch the sugar shell, and the oil’s inability to dissolve the shell itself. While still delicate, these candies can sit stable for as long as the ambient humidity allows.
The sugar used here is isomalt, so chosen because of it’s lower melting point than table sugar and also it’s resistance to caramelization (it stays perfectly clear when fully-melted, making it the sugar of choice for high-end sugar sculptures or candy casting). Maintaining the correct melted temperature was the trickiest part of this whole recipe; if the sugar is too cool, it fails to drop/stretch into a nice teardrop shape, leaving you instead with a circle-cutter-full of oil. If it’s too hot, though, it stretches so easily that it breaks, sort of like dropping oil through an actual film of bubble soap. Dicking around with the burner and moving the pot on/off of the flame as I was working added a little bit of hectic complexity to this.
elBulli’s recipe calls for a brand of European Pumpkin oil; some searching around for the brand mentioned in the recipe didn’t turn up much, but rather than get too fixated on it I decided to use what I could find here in California. The slightly-ubiquitous La Tourangelle brand of oils is something one might find at the likes of fancy-schmancy grocery shops like Whole Foods or in the ‘interesting foodstuffs’ area of Cost Plus World Market, though it seems to be almost everywhere around here. Their Pumpkin Seed oil seems slightly more rarified than some of their others, but minimal digging turned some up.
The flavor of pumpkin seed oil is lovely; it’s assertive and lasting, slightly sweet but balanced with some bitterness, and above all very flavorful. The oil combined with the sugar and a flake or two of Maldon is delicious and substantial. The sugar shell is so crisp and thin that it’s gone almost immediately, leaving just the seasoned oil to coat the mouth and linger. The real danger here in making these instead of having them served to you is overeating them; each time one of the candies broke as I was making it, I just popped it into my mouth and kept working. After about 10 of those, however, my stomach started to remind me that eating several tablespoons of oil at once probably isn’t 100% awesome.
Previous cooking experiments have left me with a cabinetful of variously-flavored oils; among these are walnut, pistachio, and almond. After (sort of) getting the hang of making the pumpkin candies, I tried making a few drops of other flavored oils. In and of themselves, walnut, pistachio, and almond oil each have recognizable and unique flavors…but I was struck at how relatively light and thin they seemed when tasted next to the pumpkin oil. The pumpkin oil is just so rich and syrupy, and a single small bite of it is satisfying and memorable. Similar bites of lighter nut oils were less interesting and less successful. It makes me wonder how long it took elBulli to get this right.