There was a time when mentioning Tom Jones would draw bemused snorts. The raw-voiced talent behind "It's Not Unusual" and "Delilah" was the king of the maligned, albeit lucrative, backwater of casino lounges. Sure, the great Welsh (how often do you get to use those words together?) legend had to dodge keys and undergarments tossed by smitten female fans. But those were performances he could, as they say, phone in.

Such is the state of Kolkovna these days. The quintessential Czech beer hall still pulls in adoring crowds. When expats treat visiting relatives to a dose of local flavor, they often choose this Old Town corner spot. But many in-the-know types are quick to suggest that Kolkovna just isn't what it used to be.

There are good items on the menu. The smoked trout filets are flakey and subjected to a gentle bath over charred wood more sweet than acrid. Quite wisely, the fish is pretty much left alone, save for a wedge of lemon on the side and a little decorative swirl of pesto. Best to nudge the citrus away — its tart acidity overpowers the delicate smoky flavor.

An order of onion rings from the list of "things to eat with beer" arrived stacked on a wooded dowel disturbingly similar to an old paper-towel dispenser. But once you get past the cutesy presentation, you have nice, crisp and comfortably greasy rings of deep-fried beer batter. All that's missing is the onion. Actually, it's in there, but it resembles shallot more than onion, bringing nothing robust or strident to counterbalance the dense batter and oil-slicked palate. Still, the breading holds together and has a character perfect for an afternoon of pilsner and people-watching. (One day, though, the kitchen will figure out that blue-cheese dressing, tart and potent, destroys everything worthwhile about onion rings.)

Another traditional companion to beer is a nicely runny round of seasoned cheese — listed on the menu as pickled brie, described as camembert and finally noted on the receipt as hermelin. Of course, culinary precision isn't part of Czech culture, and when something is cured in garlic and "chili" and glazed over with a paprika sauce, there's no point in worrying about the actual pedigree. This is an oozing mass of ripened white cheese heated until subtle flavors shrivel up, and doused in chopped red peppers — a combination that pairs well with Pilsner Urquell, as latent qualities within the amber brew rush forward to quell the little capsaicin brush fire.

By itself, though, it's just a monotonous mess.

Kolkovna runs into trouble when it hits the limitations of Czech dishes. It's not an innovative restaurant, and the dull procession of traditional fare can look tired after a few years, particularly when new places pop up and stir the pot. Yet one would think any Prague kitchen capable of turning out more palatable potato dumplings. These sticky slices of potato dough are rolled around a filling smacking of canned Bavarian ham — a bit smoky, a tad briny, with a tart undercarriage and palpable time in a processing plant, and apparently subjected to an extremely quick reheating just before delivery.

The Moravian sparrow features tender cuts of pork the size of tiny birds. They would benefit from skilled pan searing to add a meaty caramelized flavor to deepen the basic salt and pepper seasoning — otherwise they're not bad, though not really memorable, either. The red sauerkraut on one recent visit was tangy and spicy, redolent of charred cloves as if cooked in Becherovka. Too bad those white bread dumplings take up so much room.

Other favorites include the pilsner goulash, which features large cuts of tender beef, without much depth to the flavor. The roast pork hock can be extremely fatty, though it's not bad when you actually excavate a piece of meat.

My expectations that mushroom pie would break the monotony waned after a couple bites. It tastes gray, drab and overly musty. The shallots and bacon fade into rumors, and the crust traces its lineage to frozen pizza, at least in flavor and texture.