Frankly, I still don't get it. After enjoying many memorable evenings at the Cantankerous Fish since it debuted in 2003, I have yet to discover the ornery entree or annoying appetizer that inspired the restaurant's name. Admittedly, a waiter was a tad aloof, but that's no reason to blame the fish, which happens to be the focus of one of my favorite menus on Castro Street.

Last July the restaurant expanded into the adjacent retail space vacated by the Napoleon At Home gallery, and underwent a major overhaul, nearly doubling in size. The owners added tables, expanded the bar, created a lounge, built new bathrooms, erected a freestanding host station, and created an overflow/private party dining room. The menu also underwent a facelift, with new chef Ryan Fillhardt offering a satisfying range of dishes without overwhelming diners with choices.

Our first meal started with a bang when the maitre d' recommended the firecracker ahi tuna tempura roll ($7). Served on a long, rectangular plate, the roll was cut into eight seaweed-wrapped rice rounds that had been fried in a delicate batter. These were propped between two squiggles of aioli (Sirachi chili and green wasabi sauces), and garnished with a mango-pepper-onion ratatouille, which offered a nice cool-down after the spicy zing of the roll.

We also sampled a pair of bay shrimp and mango spring rolls ($9), which arrived similarly plated. They were cut into thin wedges whose extreme angles exposed a well brimming with sauteed shrimp, mango, pepper jack cheese and poblano chilies. It looked sumptuous. The deep-fried crust was dry to the touch, and the rolls were served at room temperature with sprinkled hoisin sauce and more mango ratatouille.

For the next course, we split a Caesar salad ($8), a simple preparation with just a few crisp leaves of young lettuce, thin Parmesan shavings, and an anchovy balanced on top. It was refreshing but bland, although we loved the spinach salad ($8): a cooled pile of baby spinach leaves sprinkled with candied pecans and peppery green apple juliennes, topped with mild, warm goat cheese, and dressed in a honey tarragon Dijon mixture that delivered a nice kick.

Our entrees included the andouille sausage and shrimp penne pasta ($16), served steaming in a deep, white bowl. Mild, bite-sized sausage slices were tossed with plump shrimp, penne, savory mushroom chunks and fennel leaves in a tomato cream sauce. Flavors were fresh and explosive, but the sauce dominated the palette. No matter — you'll want to sop it up with a piece of bread.

While the Cantankerous Fish's seafood jambalaya ($20) is hardly traditional, it's satisfying nonetheless. Fillhardt deemphasized the "dirty" rice — which is fluffy and dampened with a tomato broth — and loaded the plate with scallops, prawns, clams, mussels and andouille sausage. The seafood was perfectly steamed to render it meaty rather than chewy or soft.

The Southwestern snapper ($19) was a pleasant surprise. Broiled and served atop a hash featuring chorizo, portobello mushroom and red peppers, the snapper was slathered with a generous portion of tomatillo guacamole. With all three layers on a forkful, the juxtaposed tastes and textures are fantastic: from firm and fleshy snapper to smooth and refreshing guacamole, to the snap of chorizo and peppers. I'll definitely order this dish again.

I wasn't nearly as enthused about the crab-stuffed baked Idaho trout ($21), which arrived wearing its crispy skin. The fillet rested on a pool of lemon basil vinaigrette and was split down the middle, so that each bite exposed a bit more of the thin crab stuffing — which was more understated than I had hoped, though I enjoyed the zesty vinaigrette. A quartered roasted potato and ratatouille made of eggplant, zucchini, yellow squash, red onion, red bell pepper and bean sprouts accompanied the trout.

We finished with bananas Foster bread budding ($8): a mound of banana nut pudding, slightly crusty outside and chewy inside, with occasional macadamia crunches. A yummy citrus brandy was drizzled onto the pudding and an accompanying scoop of vanilla gelato, with cinnamon sprinkled over all. We also savored the decadent chocolate souffle meltaway ($8). The fluffy and rich souffle melted seductively into warm chocolate goo in the mouth, while a scoop of tart raspberry gelato provided the perfect complement. A Grand Marnier anglaise was dribbled over the top just to make it as indulgent as possible.

And speaking of indulgence, every dish we ordered came in more than an ample portion. All ingredients were uniformly fresh, the wine list offered a good selection, the redecorated ambiance was elegant — even the live music was cool. The Cantankerous Fish has always been a great dinner destination, and it's only gotten better.