A few years ago Mo Mong[1201 Westheimer, (713)524-5664] led the initial charge for upscale Vietnamese eateries. On most fronts, the restaurant has since been usurped by even more opulent pan-Asian noodle houses, but Mo Mong still clings to power by dint of its grilled pork vermicelli bowl ($6.95). Tucked behind a video store that assumed control of the Tower Theater, the minimalist-chic enclave puts a different spin on the Vietnamese comfort food. For starters, a sweeter fish sauce tops a mountain of thin noodles, cucumbers, bean sprouts, green lettuce, fried onions, cilantro and peanuts. But the real sizzle is in the pork, which is marinated for 24 hours in a mixture of soy sauce, sugar, oyster sauce, ginger and garlic, then grilled to be crispy, yet tender. Now that's using your noodle.