At the foot of the massive green wall of Forest Park, along a fast-moving highway of trucks hauling scraps of toxic garbage from here to there, sits a little white dot, a solitary food truck, that's like a lamb lost from its pod. This is Mole Prehispanic Cuisine, and it serves some of the best Southern Mexican moles and empanadas in town.

Chef-owner Luis Ochoa's cart draws from a lifetime in the restaurant industry, starting with his parents' Baja California beachside restaurant to his time as chef de cuisine at Cibo on Division Street. Inside, he crafts four distinct indigenous-style moles, none of which resembles the chocolate-sweet concoctions you see poured over enchiladas at family joints in the suburbs.

The lamb-based mole Coloradito (all are a ridiculously reasonable $8, including sides) is red as brick and has a sweet-hot note of cinnamon and clove on the finish, and the mole de Castilla is a hearty brown chicken mole with a touch of cocoa. Ochoa says his most popular dish is the mole verde, a bright-green sauce made with lightly acidic roasted tomatillos that contrast nicely against fatty Carlton Farms pork.

While the mole verde is the hit, Ochoa's favorite is the mole negro, and I'm with him on that. The mole negro is, true to its name, soot-black due to the laborious process of charring each ingredient before it's ground into the sauce. This beef-brisket dish is rich and nutty with a smoky flavor all its own, more smoldering autumn leaf pile than Carolina smokehouse.

Each mole is served with two handmade tortillas, a quinoa-and-rice mix and salad. The whole dish is then covered with neon-pink strings of pickled onion and yellow cubes of pineapple salsa, creating a synesthetic tessellation Escher would envy.

On the sides menu, there are fried plantain chips ($3) that shatter like glass, and two types of empanada ($3), including the El Jefe, which is filled with corn and poblano peppers, and the daily special, which on my visit had kabocha squash and fresh chanterelle mushrooms wrapped in buttery, golden-brown dough. Ochoa says he plans to add a vegetarian mole option to the menu.

My only quibble with Ochoa's work is that I wish he offered a salsa with a little more heat. The salsa borracha (drunk sauce) is creamy and delicious, but is relatively tame.

For now, Mole's location is lost among racing Highway 30 traffic and rail-yard noise pollution. But Ochoa says he's looking for a spot closer to town, somewhere with some foot traffic and a lunch crowd. Maybe Mississippi Avenue, maybe Montgomery Park. Wherever it lands, look for us.

Order this: Mole negro ($8).

EAT: Mole Prehispanic Cuisine, 5885 NW St. Helens Road, 875-9134. 11 am-4 pm Monday-Friday.