Wekiwa tangelos are a citrus hybrid with more grapefruit than tangerine in their genetic code. Peering into a bowl filled with their segments at Theodore Rex in Houston felt like switching on an SAD lamp. Their winter-sun shade of yellow blasted back extra bright under the lights where I sat at the restaurant’s counter, near the edge that gave way to the open kitchen. Their taste left a trace of bitter in the back of my throat; it woke me up even more than the color did. The fruit had been chilled, offset by warmed snow peas sliced into thin rectangles. Over top were half-moon slivers of tangelo rind and herb sprigs so spindly they looked almost buggy; I peered closer and saw that they were thyme leaves as deep purple as eggplant.

The dish felt like a serotonin boost in more ways than one. It was simple, beautiful, and subtly cheeky. It also signaled, early in my first meal here, that I was eating exceptional food in a style I readily recognized — everything about the plate epitomized the trademarks of Justin Yu. He’s one of our most gifted and free-thinking chefs, though I had recently wondered if I would ever taste Yu’s cooking at quite this level of sophistication again.

How would a more casual reincarnation square with Oxheart’s unique greatness?

Six years ago, in the same space Theodore Rex now occupies, Yu and his then-wife Karen Man opened Oxheart, a handsomely scruffy, 31-seat tasting menu restaurant whose vegetable-focused brilliance drew national attention to Houston’s underrated culinary culture. Oxheart’s enduring success helped propel the city further, to its current standing as America’s breakout dining destination of the decade.

In an instant I can recall some of my favorite Oxheart dishes: sauerkraut and purple hull peas in a brothy sweet pepper stew; crisp green garlic pancakes enriched with beef marrow; and chicken stuffed with rice and collard greens in a jus intensified with dried seafood. Man baked breads like black pepper pain au lait and dreamt up desserts like chocolate namelaka (a mousse-like variation on ganache) with beet crème; they always landed with a deft lightness.

Yu won the James Beard award for Best Chef: Southwest in 2016. Oxheart consistently won annual honors from the Houston Chronicle; it was a perennial on Eater’s roundup of the country’s 38 essential restaurants.

Then, in December 2016, Yu made the abrupt announcement that Oxheart would close in March 2017. He’d create a new restaurant in the same space, minus the tasting menu but serving food that was more in line with what Yu felt was his evolving style. Longtime Oxheart cook Jason White would be chef de cuisine of the new incarnation.

Many of his admirers, me included, did not receive this news happily. Oxheart’s kitchen channeled many of the defining touchstones of the 2010s: a mania for fermentation; visually arresting presentations on ceramics and flea-market china; and, especially poignant in multicultural Houston, an inclusive sense of place with regards to ingredients and cuisines. But sure, creative homeostasis can eventually thwart a restaurant, and Man was moving on as baker and pastry chef. And Yu isn’t the only one pursuing this strategy locally: Lauded chef Chris Shepherd is transforming his Houston flagship Underbelly, shifting its location and focus and turning its current home into a steakhouse.

Still, it was jarring to learn that Oxheart — Houston’s finest restaurant, and a place that broadened the definition of Texas cooking with its celebration of flora and its don’t-label-us synthesis of cuisines — would willingly dismantle itself. How would a more casual reincarnation square with Oxheart’s unique greatness?

Last October, after delays suffered in part by Hurricane Harvey flooding, Yu rebooted his Warehouse District space, naming the restaurant after his nephew Teddy. The snug, quirky room with its mismatched surfaces and a dominant U-shaped bar had molded Oxheart’s high-low identity. Yu didn’t entirely reconfigure the space, but along the longest wall he installed a banquette upholstered with a geometric, patriotic pattern of red, white, and blue triangles. The short end of the counter was lobbed off in favor of more table space; speckled tiles replaced richly grain woods in its shortened L-shape. Dome-shaped light fixtures hang from wires at different levels, creating the effect of either rising bubbles or of a bird mobile hung in a nursery. It’s still a wonky setting, though its trappings feel more comfortably grown-up.

Most welcome among the restaurant’s sights are the key staffers who’ve stuck with Yu during the transition. Front-of-house-manager Diana Kendrick sets a warm yet efficient tone for her team. Sommelier Bridget Paliwoda is as effervescent as her list of smart, mid-price sparkling varietals. She will nudge you toward eccentric natural wines, closing the deal with tastes of charmers like Partida Creus Garrut 2015, a Spanish red with the specific nuttiness of salted Marcona almonds.

That wine in particular serves as an apt pairing for Yu’s current menu, which outwardly looks to Spain, Italy, and France for inspiration but also meanders down its own idiosyncratic paths. Tomato toast, an early staple, crosses Catalan pa amb tomàquet with Italian bruschetta; slices of pain de mie are first brushed with tomato water, and then saturated with a more concentrated tomato fondant, before being crowned with cherry tomato salad. The layering of fresh and cooked flavors is pure Yu; so is the umami thunderbolt flung with each bite.

At T. Rex (as the staff calls the place), the a la carte menu clearly veers into more overtly meaty territories. A roasted Texas wagyu strip loin entree with turnips, as one example, delivers on the clear-cut pleasure principle of beef plus carbs.

Honestly, though? The cooking doesn’t veer all that far from the qualities that made Oxheart so special. The dishes are constantly, subtly changing, but I could essentially devise a DIY tasting menu from the T. Rex lineup. Based on the choices available during my dinners, the meal would kick off with the tangelo and snow pea wake-up call, and move on to buttery Charleston Gold rice and butter beans, surrounded by young lettuces and covered with puffed rice for crunch.

Then: cauliflower braised in Bordelaise sauce (veg plus marrow-boosted red wine sauce is classic Yu) and smeared with a roasted kale sauce. It looks like an unrecognizable green heap, but the harmonics make absolute sense to the taste buds. Yu, a Houston native whose family ran Cantonese restaurants, is particularly masterful with steamed seafood: On T. Rex’s menu, Gulf snapper steamed in broth with a chunky pistou made of spinach stems and covered in Meyer lemon zest and thyme leaves is a treatise on subtlety. For the final savory course, something funky: stewed brisket warmed in pickle juice, with crumbles of aged white cheddar and preserved vegetables wafting in the mix. Strange and electric and delicious.

To finish, one of two desserts on the a la carte menu. Yu spends a good chunk of his evening constructing the winner of the pair: Paris–Brest pastries piped with Swiss cheese cream and honey caramel. Its sweet-savory friction crosses wires in the brain but it works.

The shift from Oxheart to T. Rex, I think, ultimately comes down to a matter of psychology — for Yu and for diners. The cooking now is less controlled, and often wonderfully weirder, but still bears the chef’s indelible stamp.

It seems Yu needed more casual formats to exercise the culinary muscles he needed to stretch. He recently partnered with Houston bar wunderkind Bobby Heugel on a project called Better Luck Tomorrow. Bartenders pour drinks like the Mistakenly Named (rye, amaro, sweet vermouth, mint) and Yu oversees a menu of playful salads, vegetable small plates, and fried chicken variations. He’s proving himself something of a sandwich savant: Nights at Better Luck Tomorrow bring the “party melt,” with its stinging tangle of red onions and stratums of both molten and crisped cheese. During weekend brunch, his spaghetti sandwich (a Medusa mass of saucy noodles squirming between two slices of cheese toast) horrifies and delights in equal measure.

Back at T. Rex, securing prime-time reservations for the tiny room isn’t easy. Customers intimidated or put off by Oxheart’s tasting-menu format have been making their way to the restaurant; old-line devotees have mostly conceded to the changes. Why shouldn’t they? Justin Yu is still Justin Yu, and his singular, peculiar Warehouse District destination remains one of Houston’s finest restaurants.

Theodore Rex: 1302 Nance Street, Houston, TX, (832) 830-8592. Open for dinner Thursday-Monday, 5-10 p.m.

Better Luck Tomorrow: 544 Yale Street, Houston, TX, (713)802-0285. Kitchen serves food daily 3 p.m.-midnight; brunch Saturday-Sunday 11 a.m.-3:30 p.m.