Uni Pasta (Sea Urchin Cacio e Pepe)

Uni Pasta (Sea Urchin Cacio e Pepe) is a rich and creamy twist on traditional cacio e pepe. This uni pasta recipe features cheesy noodles, buttery sea urchin, and strips of salty nori (seaweed). It's an decadent seafood pasta perfect for entertaining or a date night at home.

This uni pasta was inspired by our other rich twist on cacio e pepe, Cacio e Pepe with Burrata. Uni cacio e pepe incorporates sea urchin in the creamy sauce and on top of each serving. Uni, pronounced as "oo-nee", is the Japanese word for sea urchin. It has a custard-like texture and a light sweet and salty flavor. In Japanese cuisine, this delicacy is typically enjoyed as nigiri sushi and sashimi. Its delicate texture is perfect for this uni pasta.

There are different types of uni, which vary depending on where the uni was harvested. The most common types of sea urchin include aka uni, bafun uni, ensui uni, and murasaki uni. Inside of the spiky interior of the sea urchin are five tongue-like strips of edible uni.

Fresh uni is most commonly available from early fall to late spring. Find creamy uni at your local Japanese or Asian market, specialty market, or fish monger. Some online retailers can also ship uni in chilled insulated packaging.

Jump to:

• Ingredients
• Instructions for Uni Pasta
• Substitutions
• Variations
• Equipment
• Storage
• Top tip
• Related Recipe
• Did You Like This Recipe?
• Uni Pasta (Sea Urchin Cacio e Pepe)
• Food safety

Ingredients

• Uni - Its rich ocean flavor and creamy texture pairs beautifully with traditional cacio e pepe.
• Creme fraiche - Creme Fraiche mixed with uni adds creaminess and accentuates the uni flavor. This ingredient is a thick, rich cream that is similar to sour cream, but is less tart. Learn more about the difference between creme fraiche and sour cream.
• Pasta - Pasta is essential to cacio e pepe. Cacio e pepe is best served with a thin, long noodle. The cheesy sauce easily coats the noodles, such as spaghetti or bucatini.
• Parmigiano-Reggiano - Parmigiano-Reggiano is made of unpasteurised cow's milk. It has a unique umami flavor and works with the pasta water to make the sauce creamy.
• Pecorino Romano - Pecorino Romano is a hard cheese made of sheep's milk, which gives it a uniquely sharp flavor. Parmigiano-Reggiano and Pecorino cheese give cacio e pepe its signature sharp, rich flavor. The two cheeses are often used interchangeably but are made of two types of milk and have distinct flavors.
• Freshly ground black pepper - Black pepper adds the signature spice to the pasta.
• Kosher salt - Kosher salt adds flavor to the pasta water.
• Pasta water - Pasta water is an essential ingredient for this pasta recipe. The pasta water is starchy and creates a creamy sauce when mixed with the cheese, which is why traditional cacio e pepe does not require butter.
• Butter - While traditional cacio e pepe does not call for butter, it does make it easier to achieve the creaminess of a traditional cacio e pepe.

See recipe card for quantities.

Instructions for Uni Pasta

Make the uni crème fraîche - First, add 6 tablespoons of creme fraiche and 6 pieces of uni to a food processor. Then pulse until creamy and set aside.

Cook the pasta - Second, bring 3 quarts of water to a boil in a large pot and season with kosher salt. Cook pasta for 6-7 minutes, or about a minute before al dente. Reserve 1 cup of pasta water and drain the rest. Set the pasta aside.

Prepare the pan and add pasta - Third, heat olive oil on medium heat in a skillet or non-stick pan. Then mix in pepper and cook until toasted and fragrant, about 1 minute. Then, add ½ cup of the reserved pasta water to the pan. Once the water simmers, add pasta and swirl in pasta pepper water with rubber-tipped tongs.

Add Parmigiano-Reggiano - Next, reduce the heat to low and add butter and Parmigiano-Reggiano to the pan. Use tongs to stir in the butter and cheese in a circular motion to coat the pasta.

Add Pecorino Romano and uni crème fraîche - Then remove the pan from the heat and stir in the Pecorino Romano and uni crème fraîche mixture. Use the tongs to toss the pasta until the cheese melts and the pasta is evenly coated. If the pasta is dry, stir in more pasta water one tablespoon at a time until it reaches a saucy consistency.

Serve and garnish - Finally, serve the pasta in plates or bowls and scrape the bottom of the pan with a spoon to collect the starchy sauce. Top each serving with the starchy sauce, 2 uni pieces, nori strips, and more black pepper to taste. Serve immediately and enjoy!

Hint: When cooking the pasta in a large pot, remove it from the boiling water just before it is al dente. Once you add it to the pan with the pasta water, the pasta will become al dente and finish cooking while mixing with the other ingredients.

Substitutions

• Burrata - Like uni, burrata is also creamy and delicious. Replace uni with burrata it if you don't like the ocean flavor of uni, but still want extra creaminess in your cacio e pepe. See my Cacio e Pepe with Burrata recipe here.
• Tonnarelli - Substitute this type of pasta for spaghetti if you prefer a thicker pasta. Tonnarelli, also known as spaghetti alla chitarra, is great because it has a rough and textured surface that holds onto sauces well.
• Bucatini - Instead of spaghetti, use bucatini noodles. Bucatini is a spaghetti-like noodle that has a hole in the center, which catches sauces well.
• Gluten-free Spaghetti - Use a gluten free spaghetti if you are gluten intolerant. We only recommend Garofalo Gluten Free Spaghetti, which tastes like traditional wheat based pasta.
• Homemade Pasta - Use homemade pasta from scratch instead of store bought spaghetti.

Variations

• Spicy - Add more black pepper, chili pepper flakes, or togarashi while cooking to imbue heat into the dish
• Extra creamy - Add more Parmigiano-Reggiano and Pecorino cheese to make the dish extra creamy.
• Garlic - If you want to add a hint of garlic, smash one clove and add it to the pan when you add the pasta water. Once the water simmers, remove the garlic from the pan and follow the remaining steps. This will add a hint of garlic flavor to the pasta water.
• Risotto - Instead of uni pasta, make uni risotto and stir in uni cream. Risotto takes longer to cook, so you will need to adjust the cook time for the dish. Refrigerate the uni cream mixture or make the cream when the risotto cooked and al dente. This will help to avoid spoilage.
• Seared scallops - To make the dish even more decadent, add seared scallops on top or to the side of the finished pasta dish.

Equipment

Uni pasta (sea urchin cacio e pepe) requires common kitchen essentials. To make this sauce, you need a food processor, cheese grater, tongs, measuring cup, skillet or non-stick pan, and medium pot or dutch oven. 

If you don't have a food processor, you can use a blender. Add the creme fraiche and uni to the blender and pulse until creamy. You may need to turn off the blender, remove the lid, and use a spoon or baking silicone spatula to scrape the sides and push the cream back toward the blades again. To easily capture all of the sauce from the blender, use a mini baking silicone spatula to scrape the cream from the sides of the blender walls.

Storage

Best enjoyed immediately. However, if you have leftovers, store them in an air-tight container and keep in the fridge up to one day. To reheat leftovers, heat a teaspoon of olive oil in a pan over low-medium heat. Add the leftover pasta and use tongs to gently separate the pasta in the pan to cook. Place a lid on top of the pan and allow it to reheat, about 2-3 minutes.

Top tip

Cacio e pepe is only as delicious as the ingredients you use. We recommend using authentic Parmigiano-Reggiano and Pecorino Romano, and not using cheese from the green can or it will clump.

Related Recipe

Did You Like This Recipe?

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Food safety

• Don't leave food sitting out at room temperature for extended periods
• Never leave cooking food unattended
• Use oils with high smoking point to avoid harmful compounds
• Always have good ventilation when using a gas stove

See more guidelines at USDA.gov.