I’m not super sure this is done,” says Addison Osta Smith, the reigning champion of TV’s kid cooking competition MasterChef Junior, as she hovers over a pan of magnificently glazed Chilean sea bass. She studies the fish and searches her 10-year-old brain for the perfect descriptor. “It’s a little bit too, um, jiggly.”

The cluttered kitchen in her family’s River Forest home, which Addison shares with her parents and 13-year-old sister, bears all the trappings of a normal domestic life: An algebra book sits on a side table. School artwork hangs on the walls. It’s not until I spy the exotic ingredients crowding the countertops (lemongrass stalks, kaffir limes, yuzu sauce) that it hits me: I’m in the presence of a serious culinarian.

Addison, cooking barefoot, puts the fish back into the oven. We’re preparing a variation of the dish that earned her a cool $100,000 prize on the show’s January season finale: miso black cod with bok choy and shiitake mushrooms in a coconut-ginger broth. “I wanted to incorporate some new flavors, so instead of white miso, we’re using black miso,” she explains. “It’s sweeter, so I used a little rice wine vinegar to cut it, along with some sake. Do you want to help me get started on the broth?”

I wasn’t sure what I was in for when I requested a private lesson with this bundle of cuteness. Would Addison—who showed a Jordanesque competitive streak while dispatching 23 other minicontenders—be an insufferable child prodigy trained from birth to slice, dice, and sous vide? Or, worse, would she be an overrated hack who somehow fooled the judges? Soon after she greets me at her front door (“Hi, I’m Addison!”) wearing her signature backward baseball cap, I discover she is neither of those things.

She’s really just your standard fifth grader—albeit one with the palate of James Beard and the cheery charisma of an inoffensive Paula Deen. But perhaps most impressive is her ability to teach a somewhat adequate 40-something home cook how to prepare an incredibly complex meal.

She’s patient, too. Unlike Gordon Ramsay, the resident ranter of the MasterChef franchise, Addison is gentle as she critiques my knife skills. “You’re going to want these to be uniform,” she says as I chop willy-nilly at a pile of shiitakes. “Here, I can show you.” She was slicing with her right hand, but now she holds the knife in her left. “Wow, you’re ambidextrous?” I ask. “Uh-huh.” She nods, never looking up from the cutting board.

When I ask her about the notoriously temperamental Ramsay, she says he never intimidated her. “He’s just strict,” she says. “Everyone gets mad at some point.”

The ease with which she name-drops celebrity chefs is just one of many recent changes in the middle schooler’s life. She’s cooked with show judge and fellow Chicagoan Graham Elliot at his Randolph Street restaurant, acted in a comedy pilot for ABC, and pan-fried steak Diane for host James Corden on The Late Late Show.

“Let’s just say she is very busy,” says her mother, Kathleen Osta.

So where did her daughter get her food smarts? According to Osta, it all started with exposure to high-quality ingredients in California’s crunchy Bay Area, where the family lived until two and a half years ago. (They returned to Illinois to be closer to relatives; Osta grew up in Oak Park.) One of Addison’s earliest food memories is taking produce from her first-grade school garden to a co-op pizza joint, where the chefs created pies using the kids’ harvest. “It’s the first time I remember understanding where food comes from,” she recalls.

It also helped that Addison’s parents dragged her and her sister to all sorts of ethnic restaurants when they were very young. “I probably started eating sushi the second it was OK for babies to start eating sushi,” says Addison, whose favorite food is salmon nigiri.

“During filming, people would ask me, ‘How did she learn to make this?’ ” Osta says. “And I would say, ‘She never made it. She just likes eating it.’ ”

The first dish Addison prepared on her own, at age 6, was scrambled eggs. She picked up the technique watching and helping her mother in the kitchen. It was just a matter of time before she gravitated to more involved fare, such as spicy tom yum goong soup, which the family had frequently ordered as takeout.

“It’s almost freakish, actually,” says her father, Tony Smith, about Addison’s instinctive cooking chops.

As I watch her layer the flavors of her coconut-ginger broth, I appreciate that freakishness. After we whack lemongrass on the counter, she adds the kaffir lime zest, chicken stock, ginger, sesame oil. She doesn’t once consult the crinkled recipe on the counter.

“I love coming up with new ideas,” she says, directing her attention to the veggies, which she plans to flambé in white wine, of course. (If this were MasterChef, she might have been docked points: The wine’s alcohol content isn’t high enough to ignite. Still, she somehow manages to coax a flame from the pan—and set off the smoke alarm.)

Finally, Addison meticulously plates the dish: pouring the broth around an island of jasmine rice, laying the vegetables to the side, and placing her no-longer-jiggly fish on top, tilted like a hipster’s jaunty hat.

I offer to plate the next one. Big mistake. “Have you watched everything you need to do?” she asks. Sort of. I pick up the asparagus with a fork.

“No, you’re already wrong,” she says tersely. Uh-oh. Diva alert. Maybe I misread this preteen rising star. Just then, Addison flashes another ginormous smile. She’s messing with me. She motions for me to drop the veggies and grab the ladle to pour the broth.

She may not be letting her sudden fame go to her head, but the dish? It still needs to be perfect.