In this Uni Pasta recipe, I’m going to show you the fundamental techniques you need to know to prepare this sea urchin cream sauce and the same technique can be adapted to make other similar Japanese pasta recipes like Creamy Mentaiko Spaghetti and Nori Cream Pasta.
Why This Recipe Works
Mashing the uni rather than pureeing retains some of its texture. Finishing the spaghetti in a pan like risotto by stirring it with oil and water releases starch from the noodles, allowing the two liquids to form a creamy emulsion. This creates the base for the uni cream sauce. Adding the uni cream mixture to the pasta at the very end ensures the sauce is silky smooth and does not break.
What is Uni?
Uni (うに, ウニ, or 海胆) is the Japanese word for sea urchin. It’s also the name of the edible orange or yellow roe or “coral” inside the sea urchin’s shell. Although historically, it’s been eaten by cultures worldwide, Japan is by far the largest consumer of this spiny echinoderm. Climate change has contributed to a boom in sea urchin populations around the world, and they’ve decimated kelp forests in those areas. Urchins eat the base of kelp plants, detaching them from the sea floor. Sea otters and other predators used to keep the population in check, but their numbers have been decimated by hunting. Since marine forests can sequester up to 20 times the amount of carbon per acre than their land-based equivalent, this is bad. That’s why this is one delicacy from the sea you don’t have to feel too guilty about eating.
Ingredients
Uni -This Japanese seafood pasta gets its flavor and color from uni or sea urchin roe. It’s usually sold on small wooden pallets at Japanese grocery stores, but you may also find it packed in tubs of salt water, or you may find them still in their spiny shells. Shucked uni is often treated with alum to help it retain its shape, but this can make it taste bitter. That’s why I recommend looking for untreated uni or shuck them yourself. I used Chilean uni for the sauce and uni from Hokkaido for the topping. If you’re in the US, Santa Barbara uni will work fine. If you end up with more than you need or this dish, try my Sea Urchin Ceviche; it’s a cool refreshing way to enjoy uni. Cream - Uni is quite rich on its own, and heavy cream can be cloying, so I recommend using a cream with a relatively low butterfat content. Light cream (~20% fat) or half and half (12% fat) are good options. If you can’t find light cream, you can add a splash of milk to heavy cream to lighten it up. Olive oil - I recommend using extra-virgin olive oil. A mild one made from ripe olives with a round buttery flavor works best. You want to avoid spicy or green-tasting olive oils, which can make the uni taste bitter. Garlic - Since there are no herbs or spices in this sea urchin dish, garlic joins the uni as the predominant flavor in the sauce. Anchovy - Anchovies get a bad rap for being fishy and salty, but they act as a seasoning while boosting umami when used in small quantities. I prefer anchovies packed in jars with oil rather than cans. I also try to look for anchovies that are more pink or beige in color rather than gray or dark brown. Sake - Sake is an alcoholic beverage made by fermenting rice. The fermentation process breaks down protein in the rice into its constituent amino acids, and these amino acids are what create the taste of umami. If you want to learn more about this, check out my article on the best sake for cooking and my series of videos about sake. Soy Sauce - While it may be surprising ingredient to add to pasta, soy sauce is used in many Japanese pasta dishes like Butter Shoyu Pasta to add a satisfying amount of umami to the sauce. Pasta - In Japan, Spaghetti Napolitan was one of the first pasta dishes introduced to the country and these lanky noodles are also used to make uni pasta. That being said, there’s no reason why you couldn’t use another long noodle like linguine or bucatini. I prefer thicker spaghetti (1.9mm or thicker) or spaghetti for dishes with a rich, creamy sauce like this one. Shiso - Green shiso is a Japanese varietal of perilla that’s part of the mint family. It has broad saw-toothed leaves and a bright fragrance that’s hard to compare to other herbs. If you can’t find shiso near you, you can replace it with other herbs such as tarragon, parsley, chives, or scallions.
How to Make Uni Pasta
To make the uni cream, mash ¾ of the uni with a fork or a whisk, and then stir in the cream. You can also do this by pulsing an immersion blender or food processor. Bring a pot of water water to a boil and add a generous amount of salt (1 teaspoon of salt per 10 US cups of water). Boil your spaghetti for two minutes less than the package directions (we finish cooking it in the sauce). For my spaghetti, the boiling time was eleven minutes, so I set the timer for nine minutes. When the timer is down to three minutes, add the olive oil, garlic, and anchovies to a skillet over medium-high heat. Sauté the mixture until the garlic is fragrant and cooked through, but don’t let it brown. Turn down the heat and carefully add the soy sauce. When the soy sauce has mostly evaporated, add the sake. There are two reasons for turning down the heat. The first is that adding a liquid to hot oil will spatter; the second is that the sudden release of alcohol vapors can cause it to ignite. Turn the heat up to bring the mixture to a boil and cook it until it no longer smells like alcohol. Transfer the spaghetti directly to the frying pan with tongs when the timer goes off. You also want to add a ladle of the boiling liquid to the pan. Continue cooking the spaghetti with the garlic and oil while stirring constantly. Once there is very little liquid left, add another ladleful of pasta water to the pan and repeat until it is cooked to your liking. This should take another 2-3 minutes. To finish the dish, add the uni cream and toss until the spaghetti is evenly coated and the sauce has warmed up. If the spaghetti starts to stick together or the sauce seems too thick, just add more boiling liquid to thin it out. Keep in mind that the spaghetti will continue to absorb the sauce as you plate it, so you want it to be fairly juicy. Be sure to taste your sauce for salt. Uni varies in salinity, so I’ve reduced the amount of other salty elements, but you may need to season with salt if your uni is on the mild side. Twirl the noodles in a bowl with tongs to plate it and garnish the creamy uni pasta with the reserved fresh sea urchin and green shiso.