Paseo. Mere mention of the word gets my mouth watering. The popular Seattle restaurant, with neighborhood locations in Ballard (outdoor seating only) and Fremont, inevitably has long lines of eager diners. But even before you spot the customers, you'll likely catch a whiff of caramelized onions and roasted pork wafting down the street.

The deliciously messy sandwiches are pretty straightforward and most share the same formula—namely, a "lightly toasted baguette slathered with aioli (seasoned mayo), fresh cilantro, pickled jalapeños, crisp romaine lettuce, and crowned with caramelized onions." Sounds simple, right? But when it comes to the process—from sourcing their ingredients to preparing their meats—Paseo is highly secretive. I called for information and got a couple of tidbits before I was asked to leave my number for Lorenzo Lorenzo (that's the owner's actual name!), who, I was warned, most likely wouldn't respond to sandwich-making inquiries.

Here's what I can tell you. Paseo's sandwiches come on Giuseppe rolls made by Macrina Bakery. They're soft enough to bite, but sturdy enough to hold thick slatherings of aioli and a big stack of fillings, though the strength of the bread doesn't help with the sliding out of the ingredients. The garlic flavor is pretty prominent, but doesn't overshadow the cilantro and jalapeños. Meanwhile, big circles of thick-cut Colossal onions (extracted information—even the type of onion is supposedly a secret) play an important role; the key to their caramelization, I'm told by a source, is blanching them before they're sautéed.

The Caribbean Roast is my favorite sandwich, packed with succulent pork shoulder that has a slight citrus tang. If I overlook the issue of sustainability, I also like the sandwich of Sautéed Prawns. And the Paseo Press offers some variety, substituting banana peppers for the jalapeños and delivering some good contrast in the meaty textures department.

Speaking of peppers, I'm not sure how Paseo customizes the spice level of its sandwiches other than altering the number of jalapeños, which means you're still likely to get heat in any given bite. Though it's worth noting that these jalapeños are pickled, so they pack less punch than raw ones.

Logistically, it's worth remembering that Paseo is closed on Sundays and Mondays, and management rewards workers by providing an approximately month-long winter break. And be forewarned: Paseo is cash-only, and sandwiches are subject to running out by the end of the day. Finally, the sandwiches are incredibly sloppy. The lettuce starts crisp but softens up over time, adding to a slippery, sliding sandwich experience that will have you using numerous napkins and Wet-Naps. (If you're taking Paseo on a picnic, plan accordingly.)

Admittedly, it's fun to watch and listen to people eating their sandwiches. Last visit, I witnessed a guy with greasy hands daringly lift his beverage with his wrists, while nearby one person told another, "You've got some stuff on your face." You'll happily grease up your hands and face with any of Paseo's sandwiches.

Not sure how to place your order? Taking them in menu order, check out all 11 sandwiches, with Paseo's descriptions and some additional commentary, in the slideshow»

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