Who's the biggest buyer of local produce among area chefs? It just might be Rob Uyemura.

I'd been hearing Uyemura's name with some regularity when I visited farmers markets and talked with local growers and producers. I admired his cooking from when he helped open Eau in the Chase Park Plaza about eight years ago, but neither he nor his current restaurant home, Yia Yia's, had been on my radar as a haven for locavores.

Maybe he ought to move the oversize map of his suppliers from the restaurant's waiting area out onto busy Olive Boulevard. Given the sheer size of Yia Yia's, Uyemura can probably measure his annual local purchases by the ton. More important, he hasn't lost any of the creativity that I remembered from when he was at Eau.

Sometimes he keeps the ingredients almost exclusively local, as with the panzanella ($9.99), a bread-augmented salad that shows up among the appetizers rather than the salads. The toasted bread was tossed amid cherry and full-size heirloom tomatoes in shades of orange, red and pink, The varied greens of cucumber and the purple of red onions provided further kaleidoscopic effects, with bright white homemade mozzarella for creaminess and bookends of unsmoky local bacon framing the vegetables. The bread also served as an absorbent for both the vegetable juices and for the sweet-tangy sherry vinaigrette that lightly dresses the dish.

Other times he only nods at local ingredients, as with his tuna and hamachi crudo ($13.99). If you're dogmatic about local sourcing around these parts, you're going to have a very small seafood menu. Nonetheless, more than half of the nation's horseradish comes from the area around Collinsville, and Uyemura deftly combines horseradish and ginger to add multiple layers of zip to the diced maroon and off-white raw fish. The presentation was again striking, the fish topped by strips of basil at the center of an oversize plate, and chive straws, crisps, olives and rings of a raw red chile surrounding it.

We do raise trout around these parts, so the one local seafood entrée was two headless, tailless, boneless fillets ($18.99) with a line of crisped prosciutto running the length of them, a sprinkling of fresh tarragon and a garnish of sherry-marinated orange and red cherry tomatoes. The result was a mix of sweet and salty flavors to complement the firm, mild fish. Crisp, only lightly cooked green beans were nestled underneath; they were a fine accompaniment, but their stated heirloom status didn't make them stand out from ordinary green beans.

I generally prefer grain-fed beef to grass-fed beef, but I very much enjoyed how grass-fed tastes in the chewier, more full-bodied flank steak cut ($21.99). Five long slices came almost fully hidden under corn that had been trimmed from the cob, with a striking roasted red chile on top and chile-fired, Gouda-enhanced polenta underneath — fine on its own, but also a collector for a rich meat reduction that glistened at the borders of the plate.

We hit a couple of off-notes: a camouflaged bone in an otherwise fully boned duck confit, and some asparagus, which seemed out of character for a July rendition of a summer vegetable pasta.

Yia Yia's (which, oddly, is spelled Ya Ya's all over the menu, even to the point that the logo has been altered to remove the stylized i's) is part of a minichain owned by PB&J Restaurants of Kansas City, also the original operator of Eau. The affiliation lets Uyemura expand what he can get from farm to table quickly to include suppliers in Kansas and Iowa. If you missed the map near the host's station, be sure to check out the suppliers list on the last page of the menu.