Illinois, behold: Your 700-pound state fair butter cow is here.

The Illinois State Fair’s butter cow is back in all its creamy glory.

Sculptor Sarah Pratt spent 90 hours over five days crafting the cow. The unsalted spectacle, first whipped up in 1922, has been a part of the state fair for a century. Gov. J.B. Pritzker unveiled the silky, glistening, yellow-white sculpture last week.

Before the governor pulled blues drapes aside to unshroud the bovine bust, he said he was “gobsmacked” by Pratt’s artistry.

“She doesn’t just craft us a cow. She creates an entire scene,” Pritzker said. Visitors can get their own butter cows 3D printed at the fair, he added.

The annual sculpture celebrates the state’s dairy farmers. But it’s also taken on a life of its own to become an essential stop at the Illinois fair.

Pratt found inspiration for this year’s iteration while sitting between her chicken coop and pasture, thinking about the plants in her garden and the way we connect with the Earth. In her sculpture, a nod to the fair’s “Grow with us” theme, a farmer tends to plants as a mischievous Jersey cow stands behind him.

“She’s snatched up a sunflower and it’s hanging out of her mouth,” Pratt said.

The silky, glistening cow weighs between 650 and 700 pounds, she said. The farmer adds another hundred. The concoction doesn’t squander much, though. Pratt’s cows have been built from the same glob of Prairie Farms butter, stored in an ice cream factory freezer, for the last 17 years.

[ Vintage Chicago Tribune: The history of the butter cow ]

“That’s important to me, that we’re not wasting it. It also molds better the older it is,” Pratt said.

The sculptor, who also crafts the Iowa State Fair’s butter cow, creates her masterpieces inside the display cases where they’re exhibited.

“I have tried to transport a miniature butter cow in my vehicle and, yes, I can say that that is quite terrifying,” she said.

She bundles up to piece the beast together with the temperature set to 42 degrees: warm enough to let her work the fat, but cold enough to keep things together. She uses tools similar to those needed for clay sculpting alongside a mix of mechanic-like utensils she and her predecessors have found necessary.

The livestreamed butter cow stands on a spinning platform. Pratt encourages visitors to check out every part of it.

“Get it from all angles, because it really does look so different,” she said.

Each year’s cow begins to come to life as Pratt watches dairy shows online. With a feel for what the animals look like and how they move, the artist sketches a plan and builds a steel-frame armature.

Then it’s time to slap on the butter. She starts with the ribs, and the legs go on last.

“The udder attachment on the backside of a dairy cow should be high and wide,” Pratt said. “The back is straight, with just a short incline up to the neck. You don’t want it to be bowed.”

Pratt inherited her artistic sensibilities from her mentor, Norma “Duffy” Lyon. Lyon became Iowa’s official butter cow sculptor in 1960, The Washington Post wrote when she died in June 2011.

The titan of food-based art had wanted to become a veterinarian, but Iowa State University wasn’t letting women into that college when she was in school, Pratt said. So Lyon took her sculpting classes and anatomy coursework and churned her passion for animals into something else.

The two joined forces when Pratt failed miserably at showing dairy cows at the Iowa State Gair as a teenager.

“To get me out of the barn during the day, where I wasn’t as helpful, I got to help in the butter cooler,” she said. Pratt worked as Lyon’s apprentice for the next 14 years.

This fair’s cow features 13 hidden hearts to symbolize the 13 essential nutrients in milk, she said. Hidden even deeper inside is the armature Lyon used, which Pratt recently refurbished.

“Building on that firm foundation is very symbolic for me,” Pratt said.

[ Storm kills power, but not the 2005 Illinois State Fair’s butter cow mascot ]

Pratt now mentors her twin daughters in butter cow sculpting. A few years ago, one had to write an essay about a famous Iowan and picked her mother. As Pratt’s daughter interviewed her, Pratt told her that she had really wanted to spend her life going on archaeological adventures like Indiana Jones.

“And she was like, ‘Mom, you did it … you get to do these adventures in the summer,’” Pratt said. She fought tears as she mentioned that her twins will go off to college next week, where one will work in costume design and another will study ceramics.

Afternoon Briefing

Daily

Chicago Tribune editors’ top story picks, delivered to your inbox each afternoon.

“Your plans end up coming together in such a different way than you thought possible,” she said.

The artist loves to see grandparents bringing their grandkids to see her sculpture. The students from kindergarten to third grade that Pratt teaches during the school year dote over the dairy diorama too, she said.

The state fair is in many ways about the newest things in technology and agriculture, Pratt said. There’s always something new, something bigger and better, she said. But the butter cow has been there for 100 years, and it hasn’t melted away.

“It is a time-tested tradition,” Pratt said. “A constant in a world that is ever-changing and evolving in good and confusing ways.”

You can see the butter cow at the Illinois State Fair’s Dairy Building. The fair runs through Sunday. More information can be found online.

jsheridan@chicagotribune.com

Twitter @jakesheridan_